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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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Ecker M, Schregle R, Kapoor-Kaushik N, Rossatti P, Betzler VM, Kempe D, Biro M, Ariotti N, Redpath GMI, Rossy J. SNX9-induced membrane tubulation regulates CD28 cluster stability and signalling. eLife 2022; 11:e67550. [PMID: 35050850 PMCID: PMC8786313 DOI: 10.7554/elife.67550] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Accepted: 01/12/2022] [Indexed: 12/12/2022] Open
Abstract
T cell activation requires engagement of a cognate antigen by the T cell receptor (TCR) and the co-stimulatory signal of CD28. Both TCR and CD28 aggregate into clusters at the plasma membrane of activated T cells. While the role of TCR clustering in T cell activation has been extensively investigated, little is known about how CD28 clustering contributes to CD28 signalling. Here, we report that upon CD28 triggering, the BAR-domain protein sorting nexin 9 (SNX9) is recruited to CD28 clusters at the immunological synapse. Using three-dimensional correlative light and electron microscopy, we show that SNX9 generates membrane tubulation out of CD28 clusters. Our data further reveal that CD28 clusters are in fact dynamic structures and that SNX9 regulates their stability as well as CD28 phosphorylation and the resulting production of the cytokine IL-2. In summary, our work suggests a model in which SNX9-mediated tubulation generates a membrane environment that promotes CD28 triggering and downstream signalling events.
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Affiliation(s)
- Manuela Ecker
- EMBL Australia Node in Single Molecule Science, School of Medical Sciences and the ARC Centre of Excellence in Advanced Molecular Imaging, University of New South WalesSydneyAustralia
| | - Richard Schregle
- Biotechnology Institute Thurgau (BITg) at the University of KonstanzKreuzlingenSwitzerland
- Department of Biology, University of KonstanzKonstanzGermany
| | - Natasha Kapoor-Kaushik
- Electron Microscopy Unit, Mark Wainwright Analytical Centre, University of New South WalesSydneyAustralia
| | - Pascal Rossatti
- Biotechnology Institute Thurgau (BITg) at the University of KonstanzKreuzlingenSwitzerland
| | - Verena M Betzler
- Biotechnology Institute Thurgau (BITg) at the University of KonstanzKreuzlingenSwitzerland
| | - Daryan Kempe
- EMBL Australia Node in Single Molecule Science, School of Medical Sciences and the ARC Centre of Excellence in Advanced Molecular Imaging, University of New South WalesSydneyAustralia
| | - Maté Biro
- EMBL Australia Node in Single Molecule Science, School of Medical Sciences and the ARC Centre of Excellence in Advanced Molecular Imaging, University of New South WalesSydneyAustralia
| | - Nicholas Ariotti
- Electron Microscopy Unit, Mark Wainwright Analytical Centre, University of New South WalesSydneyAustralia
- Institute for Molecular Bioscience (IMB), University of QueenslandBrisbaneAustralia
| | - Gregory MI Redpath
- EMBL Australia Node in Single Molecule Science, School of Medical Sciences and the ARC Centre of Excellence in Advanced Molecular Imaging, University of New South WalesSydneyAustralia
| | - Jeremie Rossy
- EMBL Australia Node in Single Molecule Science, School of Medical Sciences and the ARC Centre of Excellence in Advanced Molecular Imaging, University of New South WalesSydneyAustralia
- Biotechnology Institute Thurgau (BITg) at the University of KonstanzKreuzlingenSwitzerland
- Department of Biology, University of KonstanzKonstanzGermany
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3
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Dehmani S, Nerrière-Daguin V, Néel M, Elain-Duret N, Heslan JM, Belarif L, Mary C, Thepenier V, Biteau K, Poirier N, Blancho G, Haspot F. SIRPγ-CD47 Interaction Positively Regulates the Activation of Human T Cells in Situation of Chronic Stimulation. Front Immunol 2021; 12:732530. [PMID: 34925315 PMCID: PMC8671138 DOI: 10.3389/fimmu.2021.732530] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Accepted: 10/05/2021] [Indexed: 11/16/2022] Open
Abstract
A numerous number of positive and negative signals via various molecules modulate T-cell activation. Within the various transmembrane proteins, SIRPγ is of interest since it is not expressed in rodents. SIRPγ interaction with CD47 is reevaluated in this study. Indeed, we show that the anti-SIRPγ mAb clone LSB2.20 previously used by others has not been appropriately characterized. We reveal that the anti-SIRPα clone KWAR23 is a Pan anti-SIRP mAb which efficiently blocks SIRPα and SIRPγ interactions with CD47. We show that SIRPγ expression on T cells varies with their differentiation and while being expressed on Tregs, is not implicated in their suppressive functions. SIRPγ spatial reorganization at the immune synapse is independent of its interaction with CD47. In vitro SIRPα-γ/CD47 blockade with KWAR23 impairs IFN-γ secretion by chronically activated T cells. In vivo in a xeno-GvHD model in NSG mice, the SIRPγ/CD47 blockade with the KWAR23 significantly delays the onset of the xeno-GvHD and deeply impairs human chimerism. In conclusion, we have shown that T-cell interaction with CD47 is of importance notably in chronic stimulation.
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Affiliation(s)
- Safa Dehmani
- OSE Immunotherapeutics, Nantes, France.,Nantes Université, Inserm, Centre de Recherche en Transplantation et Immunologie, Unité Mixte de Recherche (UMR) 1064, Institut de Transplantation Urologie-Néphrologie (ITUN), Nantes, France
| | - Véronique Nerrière-Daguin
- Nantes Université, Inserm, Centre de Recherche en Transplantation et Immunologie, Unité Mixte de Recherche (UMR) 1064, Institut de Transplantation Urologie-Néphrologie (ITUN), Nantes, France
| | - Mélanie Néel
- Nantes Université, Inserm, Centre de Recherche en Transplantation et Immunologie, Unité Mixte de Recherche (UMR) 1064, Institut de Transplantation Urologie-Néphrologie (ITUN), Nantes, France
| | - Nathan Elain-Duret
- Nantes Université, Inserm, Centre de Recherche en Transplantation et Immunologie, Unité Mixte de Recherche (UMR) 1064, Institut de Transplantation Urologie-Néphrologie (ITUN), Nantes, France
| | - Jean-Marie Heslan
- Nantes Université, Inserm, Centre de Recherche en Transplantation et Immunologie, Unité Mixte de Recherche (UMR) 1064, Institut de Transplantation Urologie-Néphrologie (ITUN), Nantes, France
| | | | | | | | | | | | - Gilles Blancho
- Nantes Université, Inserm, Centre de Recherche en Transplantation et Immunologie, Unité Mixte de Recherche (UMR) 1064, Institut de Transplantation Urologie-Néphrologie (ITUN), Nantes, France
| | - Fabienne Haspot
- Nantes Université, Inserm, Centre de Recherche en Transplantation et Immunologie, Unité Mixte de Recherche (UMR) 1064, Institut de Transplantation Urologie-Néphrologie (ITUN), Nantes, France
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4
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Siokis A, Robert PA, Demetriou P, Dustin ML, Meyer-Hermann M. F-Actin-Driven CD28-CD80 Localization in the Immune Synapse. Cell Rep 2019; 24:1151-1162. [PMID: 30067972 DOI: 10.1016/j.celrep.2018.06.114] [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] [Received: 01/01/2018] [Revised: 04/18/2018] [Accepted: 06/28/2018] [Indexed: 12/27/2022] Open
Abstract
During immunological synapse (IS) formation, T cell receptor (TCR) signaling complexes, integrins, and costimulatory molecules exhibit a particular spatial localization. Here, we develop an agent-based model for the IS formation based on TCR peptide-bound major histocompatibility complex (pMHC) and leukocyte-function-associated antigen 1 (LFA-1) intracellular activation molecule 1 (ICAM-1) dynamics, including CD28 binding to a costimulatory ligand, coupling of molecules to the centripetal actin flow, and size-based segregation (SBS). A radial gradient of LFA-1 in the peripheral supramolecular activation cluster (pSMAC) toward the central supramolecular activation cluster (cSMAC) emerged as a combined consequence of actin binding and diffusion and modified the positioning of other molecules. The simulations predict a mechanism of CD28 movement, according to which CD28-CD80 complexes passively follow TCR-pMHC microclusters. However, the characteristic CD28-CD80 localization in a ring pattern around the cSMAC only emerges with a particular CD28-actin coupling strength that induces a centripetal motion. These results have implications for the understanding of T cell activation and fate decisions.
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Affiliation(s)
- Anastasios Siokis
- Department of Systems Immunology and Braunschweig Integrated Centre of Systems Biology, Helmholtz Centre for Infection Research, Braunschweig 38106, Germany
| | - Philippe A Robert
- Department of Systems Immunology and Braunschweig Integrated Centre of Systems Biology, Helmholtz Centre for Infection Research, Braunschweig 38106, Germany.
| | - Philippos Demetriou
- Kennedy Institute, Nuffield Department of Orthopedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Headington, Oxford OX3 7FY, UK
| | - Michael L Dustin
- Kennedy Institute, Nuffield Department of Orthopedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Headington, Oxford OX3 7FY, UK; Skirball Institute of Biomolecular Medicine, New York University School of Medicine, New York, NY 10016, USA
| | - Michael Meyer-Hermann
- Department of Systems Immunology and Braunschweig Integrated Centre of Systems Biology, Helmholtz Centre for Infection Research, Braunschweig 38106, Germany; Institute of Biochemistry, Biotechnology and Bioinformatics, Technische Universität Braunschweig, Braunschweig 38106, Germany.
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5
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McRae TD, Oleksyn D, Miller J, Gao YR. Robust blind spectral unmixing for fluorescence microscopy using unsupervised learning. PLoS One 2019; 14:e0225410. [PMID: 31790435 PMCID: PMC6886781 DOI: 10.1371/journal.pone.0225410] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Accepted: 11/02/2019] [Indexed: 11/18/2022] Open
Abstract
Due to the overlapping emission spectra of fluorophores, fluorescence microscopy images often have bleed-through problems, leading to a false positive detection. This problem is almost unavoidable when the samples are labeled with three or more fluorophores, and the situation is complicated even further when imaged under a multiphoton microscope. Several methods have been developed and commonly used by biologists for fluorescence microscopy spectral unmixing, such as linear unmixing, non-negative matrix factorization, deconvolution, and principal component analysis. However, they either require pre-knowledge of emission spectra or restrict the number of fluorophores to be the same as detection channels, which highly limits the real-world applications of those spectral unmixing methods. In this paper, we developed a robust and flexible spectral unmixing method: Learning Unsupervised Means of Spectra (LUMoS), which uses an unsupervised machine learning clustering method to learn individual fluorophores’ spectral signatures from mixed images, and blindly separate channels without restrictions on the number of fluorophores that can be imaged. This method highly expands the hardware capability of two-photon microscopy to simultaneously image more fluorophores than is possible with instrumentation alone. Experimental and simulated results demonstrated the robustness of LUMoS in multi-channel separations of two-photon microscopy images. We also extended the application of this method to background/autofluorescence removal and colocalization analysis. Lastly, we integrated this tool into ImageJ to offer an easy to use spectral unmixing tool for fluorescence imaging. LUMoS allows us to gain a higher spectral resolution and obtain a cleaner image without the need to upgrade the imaging hardware capabilities.
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Affiliation(s)
- Tristan D. McRae
- Multiphoton Research Core Facility, Shared Resource Laboratories, University of Rochester Medical Center, Rochester, NY, United States of America
- Department of Neuroscience, University of Rochester Medical Center, Rochester, NY, United States of America
| | - David Oleksyn
- Center for Vaccine Biology and Immunology and Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, NY, United States of America
| | - Jim Miller
- Center for Vaccine Biology and Immunology and Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, NY, United States of America
| | - Yu-Rong Gao
- Multiphoton Research Core Facility, Shared Resource Laboratories, University of Rochester Medical Center, Rochester, NY, United States of America
- Department of Neuroscience, University of Rochester Medical Center, Rochester, NY, United States of America
- * E-mail:
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6
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Abstract
Immune responses are controlled by the optimal balance between protective immunity and immune tolerance. T-cell receptor (TCR) signals are modulated by co-signaling molecules, which are divided into co-stimulatory and co-inhibitory molecules. By expression at the appropriate time and location, co-signaling molecules positively and negatively control T-cell differentiation and function. For example, ligation of the CD28 on T cells provides a critical secondary signal along with TCR ligation for naive T-cell activation. In contrast, co-inhibitory signaling by the CD28-B7 family is important to regulate immune homeostasis and host defense, as these signals limit the strength and duration of immune responses to prevent autoimmunity. At the same time, microorganisms or tumor cells can use these pathways to establish an immunosuppressive environment to inhibit the immune responses against themselves. Understanding these co-inhibitory pathways will support the development of new immunotherapy for the treatment of tumors and autoimmune and infectious diseases. Here, we introduce diverse molecules belonging to the members of the CD28-B7 family.
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7
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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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8
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Esensten JH, Helou YA, Chopra G, Weiss A, Bluestone JA. CD28 Costimulation: From Mechanism to Therapy. Immunity 2016; 44:973-88. [PMID: 27192564 PMCID: PMC4932896 DOI: 10.1016/j.immuni.2016.04.020] [Citation(s) in RCA: 526] [Impact Index Per Article: 65.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2015] [Indexed: 02/07/2023]
Abstract
Ligation of the CD28 receptor on T cells provides a critical second signal alongside T cell receptor (TCR) ligation for naive T cell activation. Here, we discuss the expression, structure, and biochemistry of CD28 and its ligands. CD28 signals play a key role in many T cell processes, including cytoskeletal remodeling, production of cytokines, survival, and differentiation. CD28 ligation leads to unique epigenetic, transcriptional, and post-translational changes in T cells that cannot be recapitulated by TCR ligation alone. We discuss the function of CD28 and its ligands in both effector and regulatory T cells. CD28 is critical for regulatory T cell survival and the maintenance of immune homeostasis. We outline the roles that CD28 and its family members play in human disease and we review the clinical efficacy of drugs that block CD28 ligands. Despite the centrality of CD28 and its family members and ligands to immune function, many aspects of CD28 biology remain unclear. Translation of a basic understanding of CD28 function into immunomodulatory therapeutics has been uneven, with both successes and failures. Such real-world results might stem from multiple factors, including complex receptor-ligand interactions among CD28 family members, differences between the mouse and human CD28 families, and cell-type specific roles of CD28 family members.
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Affiliation(s)
- Jonathan H Esensten
- Department of Laboratory Medicine, University of California, San Francisco, CA 94143, USA.
| | - Ynes A Helou
- Division of Rheumatology, Department of Medicine, Rosalind Russell and Ephraim P. Engleman Rheumatology Research Center, University of California, San Francisco, CA 94143, USA
| | - Gaurav Chopra
- Department of Chemistry, Purdue Center for Drug Discovery, Purdue University, West Lafayette, IN 47907, USA
| | - Arthur Weiss
- Division of Rheumatology, Department of Medicine, Rosalind Russell and Ephraim P. Engleman Rheumatology Research Center, University of California, San Francisco, CA 94143, USA; Howard Hughes Medical Institute, University of California, San Francisco, CA 94143, USA
| | - Jeffrey A Bluestone
- Diabetes Center and Department of Medicine, University of California, San Francisco, CA 94143, USA.
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9
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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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10
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Brzostek J, Gascoigne NRJ, Rybakin V. Cell Type-Specific Regulation of Immunological Synapse Dynamics by B7 Ligand Recognition. Front Immunol 2016; 7:24. [PMID: 26870040 PMCID: PMC4740375 DOI: 10.3389/fimmu.2016.00024] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Accepted: 01/18/2016] [Indexed: 01/07/2023] Open
Abstract
B7 proteins CD80 (B7-1) and CD86 (B7-2) are expressed on most antigen-presenting cells and provide critical co-stimulatory or inhibitory input to T cells via their T-cell-expressed receptors: CD28 and CTLA-4. CD28 is expressed on effector T cells and regulatory T cells (Tregs), and CD28-dependent signals are required for optimum activation of effector T cell functions. CD28 ligation on effector T cells leads to formation of distinct molecular patterns and induction of cytoskeletal rearrangements at the immunological synapse (IS). CD28 plays a critical role in recruitment of protein kinase C (PKC)-θ to the effector T cell IS. CTLA-4 is constitutively expressed on the surface of Tregs, but it is expressed on effector T cells only after activation. As CTLA-4 binds to B7 proteins with significantly higher affinity than CD28, B7 ligand recognition by cells expressing both receptors leads to displacement of CD28 and PKC-θ from the IS. In Tregs, B7 ligand recognition leads to recruitment of CTLA-4 and PKC-η to the IS. CTLA-4 plays a role in regulation of T effector and Treg IS stability and cell motility. Due to their important roles in regulating T-cell-mediated responses, B7 receptors are emerging as important drug targets in oncology. In this review, we present an integrated summary of current knowledge about the role of B7 family receptor–ligand interactions in the regulation of spatial and temporal IS dynamics in effector and Tregs.
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Affiliation(s)
- Joanna Brzostek
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine and Immunology Programme, National University of Singapore , Singapore , Singapore
| | - Nicholas R J Gascoigne
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine and Immunology Programme, National University of Singapore , Singapore , Singapore
| | - Vasily Rybakin
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine and Immunology Programme, National University of Singapore, Singapore, Singapore; Laboratory of Immunobiology, Rega Institute for Medical Research, KU Leuven, Leuven, Belgium
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11
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Bergström SE, Uzunel M, Talme T, Bergdahl E, Sundqvist KG. Antigen-induced regulation of T-cell motility, interaction with antigen-presenting cells and activation through endogenous thrombospondin-1 and its receptors. Immunology 2015; 144:687-703. [PMID: 25393517 DOI: 10.1111/imm.12424] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Revised: 10/24/2014] [Accepted: 10/30/2014] [Indexed: 12/18/2022] Open
Abstract
Antigen recognition reduces T-cell motility, and induces prolonged contact with antigen-presenting cells and activation through mechanisms that remain unclear. Here we show that the T-cell receptor (TCR) and CD28 regulate T-cell motility, contact with antigen-presenting cells and activation through endogenous thrombospondin-1 (TSP-1) and its receptors low-density lipoprotein receptor-related protein 1 (LRP1), calreticulin and CD47. Antigen stimulation induced a prominent up-regulation of TSP-1 expression, and transiently increased and subsequently decreased LRP1 expression whereas calreticulin was unaffected. This antigen-induced TSP-1/LRP1 response down-regulated a motogenic mechanism directed by LRP1-mediated processing of TSP-1 in cis within the same plasma membrane while promoting contact with antigen-presenting cells and activation through cis interaction of the C-terminal domain of TSP-1 with CD47 in response to N-terminal TSP-1 triggering by calreticulin. The antigen-induced TSP-1/LRP1 response maintained a reduced but significant motility level in activated cells. Blocking CD28 co-stimulation abrogated LRP1 and TSP-1 expression and motility. TCR/CD3 ligation alone enhanced TSP-1 expression whereas CD28 ligation alone enhanced LRP1 expression. Silencing of TSP-1 inhibited T-cell conjugation to antigen-presenting cells and T helper type 1 (Th1) and Th2 cytokine responses. The Th1 response enhanced motility and increased TSP-1 expression through interleukin-2, whereas the Th2 response weakened motility and reduced LRP1 expression through interleukin-4. Ligation of the TCR and CD28 therefore elicits a TSP-1/LRP1 response that stimulates prolonged contact with antigen-presenting cells and, although down-regulating motility, maintains a significant motility level to allow serial contacts and activation. Th1 and Th2 cytokine responses differentially regulate T-cell expression of TSP-1 and LRP1 and motility.
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Affiliation(s)
- Sten-Erik Bergström
- Department of Medicine, Karolinska Institute, Huddinge, Sweden; Department of Laboratory Medicine, Karolinska Institute, Stockholm, Sweden; Astrid Lindgren Children's Hospital, Karolinska University Hospital, Stockholm, Sweden
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12
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Santos-Argumedo L, Maravillas-Montero JL, López-Ortega O. Class I myosins in B-cell physiology: functions in spreading, immune synapses, motility, and vesicular traffic. Immunol Rev 2014; 256:190-202. [PMID: 24117822 DOI: 10.1111/imr.12105] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Myosins comprise a family of motor proteins whose role in muscle contraction and motility in a large range of eukaryotic cells has been widely studied. Although these proteins have been characterized extensively and much is known about their function in different cellular compartments, little is known about these molecules in hematopoietic cells. Myosins expressed by cells from the immune response are involved in maintaining plasma membrane tension, moving and secreting vesicles, endo- and exocytotic processes, and promoting the adhesion and motility of cells. Herein, we summarize our current understanding of class I myosins in B cells, with an emphasis on the emerging roles of these molecular motors in immune functions.
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13
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Sanchez-Lockhart M, Rojas AV, Fettis MM, Bauserman R, Higa TR, Miao H, Waugh RE, Miller J. T cell receptor signaling can directly enhance the avidity of CD28 ligand binding. PLoS One 2014; 9:e89263. [PMID: 24586641 PMCID: PMC3933428 DOI: 10.1371/journal.pone.0089263] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2013] [Accepted: 01/17/2014] [Indexed: 01/25/2023] Open
Abstract
T cell activation takes place in the context of a spatial and kinetic reorganization of cell surface proteins and signaling molecules at the contact site with an antigen presenting cell, termed the immunological synapse. Coordination of the activation, recruitment, and signaling from T cell receptor (TCR) in conjunction with adhesion and costimulatory receptors regulates both the initiation and duration of signaling that is required for T cell activation. The costimulatory receptor, CD28, is an essential signaling molecule that determines the quality and quantity of T cell immune responses. Although the functional consequences of CD28 engagement are well described, the molecular mechanisms that regulate CD28 function are largely unknown. Using a micropipet adhesion frequency assay, we show that TCR signaling enhances the direct binding between CD28 and its ligand, CD80. Although CD28 is expressed as a homodimer, soluble recombinant CD28 can only bind ligand monovalently. Our data suggest that the increase in CD28-CD28 binding is mediated through a change in CD28 valency. Molecular dynamic simulations and in vitro mutagenesis indicate that mutations at the base of the CD28 homodimer interface, distal to the ligand-binding site, can induce a change in the orientation of the dimer that allows for bivalent ligand binding. When expressed in T cells, this mutation allows for high avidity CD28–CD80 interactions without TCR signaling. Molecular dynamic simulations also suggest that wild type CD28 can stably adopt a bivalent conformation. These results support a model whereby inside-out signaling from the TCR can enhance CD28 ligand interactions by inducing a change in the CD28 dimer interface to allow for bivalent ligand binding and ultimately the transduction of CD28 costimulatory signals that are required for T cell activation.
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Affiliation(s)
- Mariano Sanchez-Lockhart
- David H Smith Center for Vaccine Biology and Immunology and Department of Microbiology and Immunology, University of Rochester, Rochester, New York, United States of America
| | - Ana V. Rojas
- Department of Biostatistics and Computational Biology, University of Rochester, Rochester, New York, United States of America
| | - Margaret M. Fettis
- David H Smith Center for Vaccine Biology and Immunology and Department of Microbiology and Immunology, University of Rochester, Rochester, New York, United States of America
| | - Richard Bauserman
- Department of Biomedical Engineering, University of Rochester, Rochester, New York, United States of America
| | - Trissha R. Higa
- David H Smith Center for Vaccine Biology and Immunology and Department of Microbiology and Immunology, University of Rochester, Rochester, New York, United States of America
| | - Hongyu Miao
- Department of Biostatistics and Computational Biology, University of Rochester, Rochester, New York, United States of America
| | - Richard E. Waugh
- Department of Biomedical Engineering, University of Rochester, Rochester, New York, United States of America
| | - Jim Miller
- David H Smith Center for Vaccine Biology and Immunology and Department of Microbiology and Immunology, University of Rochester, Rochester, New York, United States of America
- * E-mail:
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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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15
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Philipsen L, Engels T, Schilling K, Gurbiel S, Fischer KD, Tedford K, Schraven B, Gunzer M, Reichardt P. Multimolecular analysis of stable immunological synapses reveals sustained recruitment and sequential assembly of signaling clusters. Mol Cell Proteomics 2013; 12:2551-67. [PMID: 23754785 DOI: 10.1074/mcp.m112.025205] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The formation of the immunological synapse between T cells and antigen-presenting cells (APC) begins within minutes of contact and can take hours for full T-cell activation. Although early phases of the synapse have been extensively studied for a select number of proteins, later phases have not yet been examined in detail. We studied the signaling network in stable synapses by measuring the simultaneous localization of 25 signaling and structural molecules over 2 h at the level of individual synapses using multi-epitope ligand cartography (MELC). Signaling proteins including phospho(p)ZAP70, pSLP76, pCD3ζ, and pLAT, along with proteins that influence synapse structure such as F-actin, tubulin, CD45, and ICAM-1, were localized in images of synapses and revealed the multidimensional construction of a mature synapse. The construction of the stable synapse included intense early TCR signaling, a phase of recruitment of structural proteins, and a sustained increase in signaling molecules and colocalization of TCR and pLAT signaling clusters in the center of the synapse. Consolidation of TCR and associated proteins resulted in formation of a small number of discrete synaptic microclusters. Development of synapses and cSMAC composition was greatly affected by the absence of Vav1, with an associated loss in PLCγ1 recruitment, pSLP76, and increased CXCR4. Together, these data demonstrate the use of multi-epitope ligand cartography to quantitatively analyze synapse formation and reveal successive recruitment of structural and signaling proteins and sustained phosphorylation at the mature synapse.
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Affiliation(s)
- Lars Philipsen
- Otto von Guericke University, Institute of Molecular and Clinical Immunology, Leipziger Str. 44, 39120 Magdeburg, Germany
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Lim TS, Goh JKH, Mortellaro A, Lim CT, Hämmerling GJ, Ricciardi-Castagnoli P. CD80 and CD86 differentially regulate mechanical interactions of T-cells with antigen-presenting dendritic cells and B-cells. PLoS One 2012; 7:e45185. [PMID: 23024807 PMCID: PMC3443229 DOI: 10.1371/journal.pone.0045185] [Citation(s) in RCA: 102] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2012] [Accepted: 08/13/2012] [Indexed: 01/17/2023] Open
Abstract
Functional T-cell responses are initiated by physical interactions between T-cells and antigen-presenting cells (APCs), including dendritic cells (DCs) and B-cells. T-cells are activated more effectively by DCs than by B-cells, but little is known about the key molecular mechanisms that underpin the particular potency of DC in triggering T-cell responses. To better understand the influence of physical intercellular interactions on APC efficacy in activating T-cells, we used single cell force spectroscopy to characterize and compare the mechanical forces of interactions between DC:T-cells and B:T-cells. Following antigen stimulation, intercellular interactions of DC:T-cell conjugates were stronger than B:T-cell interactions. DCs induced higher levels of T-cell calcium mobilization and production of IL-2 and IFNγ than were elicited by B-cells, thus suggesting that tight intercellular contacts are important in providing mechanically stable environment to initiate T-cell activation. Blocking antibodies targeting surface co-stimulatory molecules CD80 or CD86 weakened intercellular interactions and dampen T-cell activation, highlighting the amplificatory roles of CD80/86 in regulating APC:T-cell interactions and T-cell functional activation. The variable strength of mechanical forces between DC:T-cells and B:T-cell interactions were not solely dependent on differential APC expression of CD80/86, since DCs were superior to B-cells in promoting strong interactions with T-cells even when CD80 and CD86 were inhibited. These data provide mechanical insights into the effects of co-stimulatory molecules in regulating APC:T-cell interactions.
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Affiliation(s)
- Tong Seng Lim
- Singapore Immunology Network, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore
- * E-mail: (PR-C); (TSL)
| | - James Kang Hao Goh
- Singapore Immunology Network, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore
| | - Alessandra Mortellaro
- Singapore Immunology Network, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore
| | - Chwee Teck Lim
- Mechanobiology Institute, National University of Singapore, Singapore, Singapore
- Department of Bioengineering & Department of Mechanical Engineering, National University of Singapore, Singapore, Singapore
| | - Günter J. Hämmerling
- Division of Molecular Immunology, German Cancer Research Center DKFZ, Heidelberg, Germany
| | - Paola Ricciardi-Castagnoli
- Singapore Immunology Network, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore
- * E-mail: (PR-C); (TSL)
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17
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Pagán AJ, Pepper M, Chu HH, Green JM, Jenkins MK. CD28 promotes CD4+ T cell clonal expansion during infection independently of its YMNM and PYAP motifs. THE JOURNAL OF IMMUNOLOGY 2012; 189:2909-17. [PMID: 22896637 DOI: 10.4049/jimmunol.1103231] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
CD28 is required for maximal proliferation of CD4+ T cells stimulated through their TCRs. Two sites within the cytoplasmic tail of CD28, a YMNM sequence that recruits PI3K and activates NF-κB and a PYAP sequence that recruits Lck, are candidates as transducers of the signals responsible for these biological effects. We tested this proposition by tracking polyclonal peptide:MHCII-specific CD4+ T cells in vivo in mice with mutations in these sites. Mice lacking CD28 or its cytoplasmic tail had the same number of naive T cells specific for a peptide:MHCII ligand as wild-type mice. However, the mutant cells produced one tenth as many effector and memory cells as wild-type T cells after infection with bacteria expressing the antigenic peptide. Remarkably, T cells with a mutated PI3K binding site, a mutated PYAP site, or both mutations proliferated to the same extent as wild-type T cells. The only observed defect was that T cells with a mutated PYAP or Y170F site proliferated even more weakly in response to peptide without adjuvant than wild-type T cells. These results show that CD28 enhances T cell proliferation during bacterial infection by signals emanating from undiscovered sites in the cytoplasmic tail.
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Affiliation(s)
- Antonio J Pagán
- Department of Microbiology, University of Minnesota Medical School, Minneapolis, MN 55455, USA
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18
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Abstract
The interaction between T cells and APCs bearing cognate antigen results in the formation of an immunological synapse (IS). During this process, many receptors and signaling proteins segregate to regions proximal to the synapse. This protein movement is thought to influence T cell function. However, some proteins are transported away from the IS, which is controlled in part by ERM family proteins. Tim-1 is a transmembrane protein with co-stimulatory functions that is found on many immune cells, including T cells. However, the expression pattern of Tim-1 on T cells upon activation by APCs has not been explored. Interestingly, in this study we demonstrate that the majority of Tim-1 on activated T cells is excluded from the IS. Tim-1 predominantly resides outside of the IS, and structure/function studies indicate that the cytoplasmic tail influences Tim-1 polarization. Specifically, a putative ERM binding motif (KRK 244-246) in the Tim-1 cytoplasmic tail appears necessary for proper Tim-1 localization. Furthermore, mutation of the KRK motif results in enhanced early tyrosine phosphorylation downstream of TCR/CD28 stimulation upon ectopic expression of Tim-1. Paradoxically however, the KRK motif is necessary for Tim-1 co-stimulation of NFAT/AP-1 activation and co-stimulation of cytokine production. This work reveals unexpected complexity underlying Tim-1 localization and suggests potentially novel mechanisms by which Tim-1 modulates T cell activity.
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Affiliation(s)
- Jean Lin
- University of Pittsburgh Medical Scientist Training Program and Graduate Program in Immunology, Pittsburgh, 15261, USA
| | - Leo Chen
- Department of Immunology, University of Pittsburgh School of Medicine, Pittsburgh, 15261, USA
| | - Lawrence P Kane
- Department of Immunology, University of Pittsburgh School of Medicine, Pittsburgh, 15261, USA
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Sanchez-Lockhart M, Kim M, Miller J. Cutting edge: A role for inside-out signaling in TCR regulation of CD28 ligand binding. THE JOURNAL OF IMMUNOLOGY 2011; 187:5515-9. [PMID: 22068237 DOI: 10.4049/jimmunol.1102497] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Efficient T cell activation depends on the engagement of both TCR and CD28, although the molecular mechanisms that control this signal integration are not fully understood. Using fluorescence resonance energy transfer, we show that T cell activation can drive a reorientation of the cytosolic tails of the CD28 dimer. However, this is not mediated through CD28 ligand binding. Rather, TCR signaling itself mediates this conformation change in CD28. We also show that TCR signaling can induce CD28-ligand interactions. Although the CD28 dimer appears to bind ligand monovalently in solution, we show that both ligand binding sites are required to efficiently recruit CD28 to the immunological synapse. These results suggest, that analogous to the cross-talk from TCR that regulates integrin activation, TCR-initiated inside-out signaling may induce a conformational change to the extracellular domains of CD28, enabling ligand binding and initiating CD28 signaling.
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Affiliation(s)
- Mariano Sanchez-Lockhart
- David H Smith Center for Vaccine Biology and Immunology, Aab Institute of Biomedical Sciences, University of Rochester Medical Center, Rochester, NY 14642, USA
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21
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Kong KF, Yokosuka T, Canonigo-Balancio AJ, Isakov N, Saito T, Altman A. A motif in the V3 domain of the kinase PKC-θ determines its localization in the immunological synapse and functions in T cells via association with CD28. Nat Immunol 2011; 12:1105-12. [PMID: 21964608 PMCID: PMC3197934 DOI: 10.1038/ni.2120] [Citation(s) in RCA: 118] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2011] [Accepted: 08/29/2011] [Indexed: 12/13/2022]
Abstract
Protein kinase C-θ (PKC-θ) translocates to the center of the immunological synapse, but the underlying mechanism and its importance in T cell activation are unknown. Here we found that the V3 domain of PKC-θ was necessary and sufficient for localization to the immunological synapse mediated by association with the coreceptor CD28 and dependent on the kinase Lck. We identified a conserved proline-rich motif in V3 required for association with CD28 and immunological synapse localization. We found association with CD28 to be essential for PKC-θ-mediated downstream signaling and the differentiation of T helper type 2 cells (T(H)2 cells) and interleukin 17-producing helper T cells (T(H)17 cells) but not of T helper type 1 cells (T(H)1 cells). Ectopic expression of V3 sequestered PKC-θ from the immunological synapse and interfered with its functions. Our results identify a unique mode of CD28 signaling, establish a molecular basis for the immunological synapse localization of PKC-θ and indicate V3-based 'decoys' may be therapeutic modalities for T cell-mediated inflammatory diseases.
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Affiliation(s)
- Kok-Fai Kong
- Division of Cell Biology, La Jolla Institute for Allergy and Immunology, La Jolla, California, USA
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22
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Hinterberger M, Wirnsberger G, Klein L. B7/CD28 in central tolerance: costimulation promotes maturation of regulatory T cell precursors and prevents their clonal deletion. Front Immunol 2011; 2:30. [PMID: 22566820 PMCID: PMC3341949 DOI: 10.3389/fimmu.2011.00030] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2011] [Accepted: 07/14/2011] [Indexed: 12/16/2022] Open
Abstract
According to the “two-step model,” the intrathymic generation of CD4+ regulatory T (Treg) cells segregates into a first, T cell receptor (TCR)-driven phase and a second, cytokine-dependent phase. The initial TCR stimulus gives rise to a CD25+Foxp3− developmental intermediate. These precursors subsequently require cytokine signaling to establish the mature CD25+Foxp3+ Treg cell phenotype. In addition, costimulation via CD28/B7 (CD80/86) axis is important for the generation of a Treg cell repertoire of normal size. Recent data suggest that CD28 or B7 deficient mice lack CD25+Foxp3− Treg cell progenitors. However, these data leave open whether costimulation is also required at subsequent stages of Treg differentiation. Also, the fate of “presumptive” Treg cells carrying a permissive TCR specificity in the absence of costimulation remains to be established. Here, we have used a previously described TCR transgenic model of agonist-driven Treg differentiation in order to address these issues. Intrathymic adoptive transfer of Treg precursors indicated that costimulation is dispensable once the intermediate CD25+Foxp3− stage has been reached. Furthermore, lack of costimulation led to the physical loss of presumptive Treg cells rather than their escape from central tolerance and differentiation into the conventional CD4+ T cell lineage. Our findings suggest that CD28 signaling does not primarily operate through enhancing the TCR signal strength in order to pass the threshold intensity required to initiate Treg cell specification. Instead, costimulation seems to deliver unique and qualitatively distinct signals that coordinately foster the developmental progression of Treg precursors and prevent their negative selection.
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23
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Larbi A, Pawelec G, Wong SC, Goldeck D, Tai JJY, Fulop T. Impact of age on T cell signaling: a general defect or specific alterations? Ageing Res Rev 2011; 10:370-8. [PMID: 20933612 DOI: 10.1016/j.arr.2010.09.008] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2010] [Revised: 09/22/2010] [Accepted: 09/24/2010] [Indexed: 01/09/2023]
Abstract
Decreased immune responsiveness associated with aging is generally termed "immunosenescence". Several theories have been proposed to explain age-related declines in immune responses. Here, we will focus on and describe potential defects in T cell signal transduction from the membrane to the nucleus, leading to changes in the type, intensity and duration of the response as a major factor contributing to immunosenescence. We will first detail T cell signaling through the T cell receptor (TCR), CD28 and IL-2 receptor (IL-2R) and then discuss the observed age-related alterations to these signaling pathways. The role of membrane rafts in T cell signaling and T cell aging will be described. These factors will be considered in the context of the notion that age-related changes to T cell signaling may be attributed to changes in the functionality of the T cells due to shifts in T cell subpopulations with age. For this reason, we conclude by highlighting the application of multiparametric signaling analysis in leukocyte subsets using flow cytometry as a means to obtain a clearer picture with respect to age-related changes to immune signaling.
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Muscolini M, Sajeva A, Caristi S, Tuosto L. A novel association between filamin A and NF-κB inducing kinase couples CD28 to inhibitor of NF-κB kinase α and NF-κB activation. Immunol Lett 2011; 136:203-12. [PMID: 21277899 DOI: 10.1016/j.imlet.2011.01.011] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2010] [Revised: 01/13/2011] [Accepted: 01/16/2011] [Indexed: 12/13/2022]
Abstract
CD28 costimulatory molecule plays a critical role in the activation of NF-κB. Indeed, while stimulation of T cells with either professional APCs or anti-TCR plus anti-CD28 antibodies efficiently activates NF-κB, TCR alone fails to do that. Moreover, CD28 stimulation by B7 in the absence of TCR may activate IκB kinase α (IKKα) and a non-canonical NF-κB2-like pathway, in human primary CD4(+) T cells. Despite its functional relevance in NF-κB activation, the molecules connecting autonomous CD28-mediated signals to IKKα and NF-κB activation remain still unknown. In searching for specific upstream activators linking CD28 to the IKKα/NF-κB cascade, we identify a novel constitutive association between filamin A (FLNa) and the NF-κB inducing kinase (NIK), in both Jurkat and human primary T cells. Following CD28 engagement by B7, in the absence of TCR, FLNa-associated NIK is activated and induces IKKα kinase activity. Both proline (P(208)YAP(211)P(212)) and tyrosine residues (Y(206)QPY(209)APP) within the C-terminal proline-rich motif of CD28 are involved in the recruitment of FLNa/NIK complexes to the membrane as well as in the activation of NIK and IKKα.
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Affiliation(s)
- Michela Muscolini
- Istituto Pasteur-Fondazione Cenci Bolognetti, Department of Biology and Biotechnology Charles Darwin, Sapienza University, Rome, Italy
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25
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Tuosto L. NF-κB family of transcription factors: Biochemical players of CD28 co-stimulation. Immunol Lett 2011; 135:1-9. [DOI: 10.1016/j.imlet.2010.09.005] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2010] [Revised: 09/09/2010] [Accepted: 09/14/2010] [Indexed: 12/31/2022]
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26
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Chmielewski M, Hombach AA, Abken H. CD28 cosignalling does not affect the activation threshold in a chimeric antigen receptor-redirected T-cell attack. Gene Ther 2010; 18:62-72. [PMID: 20944680 DOI: 10.1038/gt.2010.127] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Adoptive immunotherapy of cancer using chimeric antigen receptor (CAR)-engineered T cells with redirected specificity showed efficacy in recent trials. In preclinical models, 'second-generation' CARs with CD28 costimulatory domain in addition to CD3ζ performed superior in redirecting T-cell effector functions and survival. Whereas CD28 costimulation sustains physiological T-cell receptor (TCR)-CD3 activation of naïve T cells, the impact of CD28 cosignalling on the threshold of CAR-mediated activation of pre-stimulated T cells without B7-CD28 recruitment remained unclear. Using CARs of different binding affinities, but same epitope specificity, we demonstrate that CD28 cosignalling neither lowered the antigen threshold nor the binding affinity for redirected T-cell activation. 'Affinity ceiling' above which increase in affinity does not increase T-cell activation was not altered. Accordingly, redirected tumor cell killing depended on the binding affinity but was likewise effective for CD3ζ and CD28-CD3ζ CARs. In contrast to CD3ζ, CD28-CD3ζ CAR-driven activation was not increased further by CD28-B7 engagement. However, CD28 cosignalling, which is required for interleukin-2 induction could not be replaced by high-affinity CD3ζ CAR binding or high-density antigen engagement. We conclude that CD28 CAR cosignalling does not alter the activation threshold but redirects T-cell effector functions.
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Affiliation(s)
- M Chmielewski
- Zentrum für Molekulare Medizin Köln, and Tumorgenetik, Klinik I für Innere Medizin, Uniklinik Köln, Köln, Germany
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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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28
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Abstract
CD28 costimulation regulates a wide range of cellular processes, from proliferation and survival to promoting the differentiation of specialized T-cell subsets. Since first being identified over 20 years ago, CD28 has remained a subject of intense study because of its profound consequences on T cell function and its potential for therapeutic manipulation. In this review we highlight the signaling cascades initiated by the major signaling motifs in CD28, focusing on PI-3 kinase-dependent and -independent pathways and how these are linked to specific cellular outcomes. Recent studies using gene targeted knockin mice have clarified the relative importance of these motifs on in vivo immune responses; however, much remains to be elucidated. Understanding the mechanism behind costimulation holds great potential for development of new clinically relevant reagents, a fact beginning to be realized with the advent of drugs that prevent CD28 ligation and signaling.
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Affiliation(s)
- Jonathan S Boomer
- Department of Internal Medicine, Washington University School of Medicine, St Louis, Missouri 63110, USA
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29
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Deenick EK, Po L, Chapatte L, Murakami K, Lu YC, Elford AR, Saibil SD, Ruland J, Gerondakis S, Mak TW, Ohashi PS. c-Rel phenocopies PKCtheta but not Bcl-10 in regulating CD8+ T-cell activation versus tolerance. Eur J Immunol 2010; 40:867-77. [PMID: 19950170 DOI: 10.1002/eji.200939445] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Elucidating the signaling events that promote T-cell tolerance versus activation provides important insights for manipulating immunity in vivo. Previous studies have suggested that the absence of PKCtheta results in the induction of anergy and that the balance between the induction of the transcription factors NFAT, AP1 and NF-kappaB plays a key role in determining whether T-cell anergy or activation is induced. Here, we examine whether Bcl-10 and specific family members of NF-kappaB act downstream of PKCtheta to alter CD8(+) T-cell activation and/or anergy. We showed that T cells from mice deficient in c-Rel but not NF-kappaB1 (p50) have increased susceptibility to the induction of anergy, similar to T cells from PKCtheta-deficient mice. Surprisingly T cells from Bcl-10-deficient mice showed a strikingly different phenotype to the PKCtheta-deficient T cells, with a severe block in TCR-mediated activation. Furthermore, we have also shown that survival signals downstream of NF-kappaB, are uncoupled from signals that mediate T-cell anergy. These results suggest that c-Rel plays a critical role downstream of PKCtheta in controlling CD8(+) T-cell anergy induction.
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Affiliation(s)
- Elissa K Deenick
- Campbell Family Institute, Ontario Cancer Institute, University of Toronto, Toronto, ON, Canada.
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30
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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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31
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Okkenhaug K, Fruman DA. PI3Ks in lymphocyte signaling and development. Curr Top Microbiol Immunol 2010; 346:57-85. [PMID: 20563708 DOI: 10.1007/82_2010_45] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Lymphocyte development and function are regulated by tyrosine kinase and G-protein coupled receptors. Each of these classes of receptors activates phosphoinositide 3-kinase (PI3K). In this chapter, we summarize current understanding of how PI3K contributes to key aspects of the adaptive immune system.
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Affiliation(s)
- Klaus Okkenhaug
- Laboratory of Lymphocyte Signalling and Development, The Babraham Institute, Cambridge, UK.
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32
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Abstract
CD4(+) T cells engage different activating cells during their generation in the bone marrow and thymus and during their homeostasis and activation in the periphery. During these processes, T cells or their precursors establish a molecular platform for communication in the interface between the two cells that is called immune synapse (IS). Here we review the current knowledge about those different IS. Apart from looking at the structure and signalling of the IS from the T cell region, we will also focus on the area of the IS partner, mostly antigen-presenting cells (APC). We will discuss the features of different APC and their role played in the control of the resulting activated or differentiated T cell. We will also demonstrate that despite 10 years of research into the subject, large areas of this field are yet to be explored. This will keep us busy for the years to come - new exciting results lie ahead of us.
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Affiliation(s)
- Peter Reichardt
- Otto-von-Guericke University, Institute of Molecular and Clinical Immunology, D-39120, Magdeburg, Germany
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33
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Abstract
SUMMARY T-cell activation is mediated by antigen-specific signals from the TCRzeta/CD3 and CD4-CD8-p56lck complexes in combination with additional co-signals provided by coreceptors such as CD28, inducible costimulator (ICOS), cytotoxic T-lymphocyte antigen-4 (CTLA-4), programmed death (PD-1), and others. CD28 and ICOS provide positive signals that promote and sustain T-cell responses, while CTLA-4 and PD-1 limit responses. The balance between stimulatory and inhibitory co-signals determines the ultimate nature of T-cell responses where response to foreign pathogen is achieved without excess inflammation and autoimmunity. In this review, we outline the current knowledge of the CD28 and CTLA-4 signaling mechanisms [involving phosphatidylinositol 3 kinase (PI3K), growth factor receptor-bound protein 2 (Grb2), Filamin A, protein kinase C theta (PKCtheta), and phosphatases] that control T-cell immunity. We also present recent findings on T-cell receptor-interacting molecule (TRIM) regulation of CTLA-4 surface expression, and a signaling pathway involving CTLA-4 activation of PI3K and protein kinase B (PKB)/AKT by which cell survival is ensured under conditions of anergy induction.
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Affiliation(s)
- Christopher E Rudd
- Department of Pathology, Cell Signalling Section, University of Cambridge, Cambridge, UK.
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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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