1
|
Aydin S, Pareja J, Schallenberg VM, Klopstein A, Gruber T, Page N, Bouillet E, Blanchard N, Liblau R, Körbelin J, Schwaninger M, Johnson AJ, Schenk M, Deutsch U, Merkler D, Engelhardt B. Antigen recognition detains CD8 + T cells at the blood-brain barrier and contributes to its breakdown. Nat Commun 2023; 14:3106. [PMID: 37253744 PMCID: PMC10229608 DOI: 10.1038/s41467-023-38703-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2023] [Accepted: 05/09/2023] [Indexed: 06/01/2023] Open
Abstract
Blood-brain barrier (BBB) breakdown and immune cell infiltration into the central nervous system (CNS) are early hallmarks of multiple sclerosis (MS). High numbers of CD8+ T cells are found in MS lesions, and antigen (Ag) presentation at the BBB has been proposed to promote CD8+ T cell entry into the CNS. Here, we show that brain endothelial cells process and cross-present Ag, leading to effector CD8+ T cell differentiation. Under physiological flow in vitro, endothelial Ag presentation prevented CD8+ T cell crawling and diapedesis resulting in brain endothelial cell apoptosis and BBB breakdown. Brain endothelial Ag presentation in vivo was limited due to Ag uptake by CNS-resident macrophages but still reduced motility of Ag-specific CD8+ T cells within CNS microvessels. MHC class I-restricted Ag presentation at the BBB during neuroinflammation thus prohibits CD8+ T cell entry into the CNS and triggers CD8+ T cell-mediated focal BBB breakdown.
Collapse
Affiliation(s)
- Sidar Aydin
- Theodor Kocher Institute, University of Bern, Bern, Switzerland
| | - Javier Pareja
- Theodor Kocher Institute, University of Bern, Bern, Switzerland
| | | | | | - Thomas Gruber
- Institute of Pathology, Experimental Pathology, University of Bern, Bern, Switzerland
| | - Nicolas Page
- Department of Pathology and Immunology, Division of Clinical Pathology, University and University Hospitals of Geneva, Geneva, Switzerland
| | - Elisa Bouillet
- Theodor Kocher Institute, University of Bern, Bern, Switzerland
| | - Nicolas Blanchard
- Toulouse Institute for infectious and inflammatory diseases, University of Toulouse, CNRS, INSERM, UPS, Toulouse, France
| | - Roland Liblau
- Toulouse Institute for infectious and inflammatory diseases, University of Toulouse, CNRS, INSERM, UPS, Toulouse, France
| | - Jakob Körbelin
- Department of Oncology, Hematology and Bone Marrow Transplantation, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Markus Schwaninger
- Institute for Experimental and Clinical Pharmacology and Toxicology, Center of Brain, Behavior and Metabolism, University of Lübeck, Lübeck, Germany
| | - Aaron J Johnson
- Mayo Clinic Graduate School of Biomedical Sciences, College of Medicine, Mayo Clinic, Rochester, MN, USA
| | - Mirjam Schenk
- Institute of Pathology, Experimental Pathology, University of Bern, Bern, Switzerland
| | - Urban Deutsch
- Theodor Kocher Institute, University of Bern, Bern, Switzerland
| | - Doron Merkler
- Department of Pathology and Immunology, Division of Clinical Pathology, University and University Hospitals of Geneva, Geneva, Switzerland
| | | |
Collapse
|
2
|
Kumari S, Mak M, Poh YC, Tohme M, Watson N, Melo M, Janssen E, Dustin M, Geha R, Irvine DJ. Cytoskeletal tension actively sustains the migratory T-cell synaptic contact. EMBO J 2020; 39:e102783. [PMID: 31894880 PMCID: PMC7049817 DOI: 10.15252/embj.2019102783] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Revised: 11/12/2019] [Accepted: 11/18/2019] [Indexed: 01/06/2023] Open
Abstract
When migratory T cells encounter antigen-presenting cells (APCs), they arrest and form radially symmetric, stable intercellular junctions termed immunological synapses which facilitate exchange of crucial biochemical information and are critical for T-cell immunity. While the cellular processes underlying synapse formation have been well characterized, those that maintain the symmetry, and thereby the stability of the synapse, remain unknown. Here we identify an antigen-triggered mechanism that actively promotes T-cell synapse symmetry by generating cytoskeletal tension in the plane of the synapse through focal nucleation of actin via Wiskott-Aldrich syndrome protein (WASP), and contraction of the resultant actin filaments by myosin II. Following T-cell activation, WASP is degraded, leading to cytoskeletal unraveling and tension decay, which result in synapse breaking. Thus, our study identifies and characterizes a mechanical program within otherwise highly motile T cells that sustains the symmetry and stability of the T cell-APC synaptic contact.
Collapse
Affiliation(s)
- Sudha Kumari
- Koch Institute of Integrative Research, MIT, Cambridge, MA, USA.,Ragon Institute of Harvard, MIT and MGH, Cambridge, MA, USA
| | - Michael Mak
- Department of Mechanical Engineering, MIT, Cambridge, MA, USA
| | - Yeh-Chuin Poh
- Koch Institute of Integrative Research, MIT, Cambridge, MA, USA.,Department of Mechanical Engineering, MIT, Cambridge, MA, USA
| | - Mira Tohme
- Division of Immunology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Nicki Watson
- Whitehead Institute of Biomedical Research, Cambridge, MA, USA
| | - Mariane Melo
- Koch Institute of Integrative Research, MIT, Cambridge, MA, USA.,Ragon Institute of Harvard, MIT and MGH, Cambridge, MA, USA
| | - Erin Janssen
- Division of Immunology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Michael Dustin
- Kennedy Institute of Rheumatology, University of Oxford, Oxford, UK
| | - Raif Geha
- Division of Immunology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Darrell J Irvine
- Koch Institute of Integrative Research, MIT, Cambridge, MA, USA.,Ragon Institute of Harvard, MIT and MGH, Cambridge, MA, USA.,Department of Biological Engineering, MIT, Cambridge, MA, USA.,Howard Hughes Medical Institute, Chevy Chase, MD, USA
| |
Collapse
|
3
|
Norose K, Kikumura A, Luster AD, Hunter CA, Harris TH. CXCL10 is required to maintain T-cell populations and to control parasite replication during chronic ocular toxoplasmosis. Invest Ophthalmol Vis Sci 2011; 52:389-98. [PMID: 20811054 DOI: 10.1167/iovs.10-5819] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
PURPOSE Toxoplasma gondii is a major cause of ocular disease, which can lead to permanent vision loss in humans. T cells are critically involved in parasite control, but little is known about the molecules that promote T-cell trafficking and migration in the retina. Thus, the aim of this study was to image and dissect the T-cell response during chronic toxoplasmic retinochoroiditis. METHODS C57BL/6 mice were infected with the Me49 strain of T. gondii, and T cells that infiltrated the eye were analyzed by flow cytometry and imaged using multiphoton microscopy. IFN-γ, CXCL9, CXCL10, and CXCR3 mRNA levels were measured by real-time PCR. To investigate the role of CXCL10, mice were treated with anti-CXCL10 antibodies, and histopathology and immunohistochemistry were performed to monitor changes in pathology, cellular infiltration, and parasite burden in the eye. RESULTS Infection with T. gondii leads to the infiltration of highly activated motile T cells into the eye. These cells express CXCR3 and are capable of producing IFN-γ and TNF-α, and CD8+ T cells express granzyme B. The expression of CXCL9 and CXCL10 in the retina was significantly upregulated during chronic infection. Treatment of chronically infected mice with anti-CXCL10 antibodies led to decreases in the numbers of CD3+, CD4+, and CD8+ T cells and the amount of IFN-γ mRNA expression in the retina and an increase in replicating parasites and ocular pathology. CONCLUSIONS The maintenance of the T-cell response and the control of T. gondii in the eye during chronic infection is dependent on CXCL10.
Collapse
Affiliation(s)
- Kazumi Norose
- Department of Infection and Host Defense, Graduate School of Medicine, Chiba University, Chiba, Japan
| | | | | | | | | |
Collapse
|
4
|
Abstract
The phosphoinositide 3-kinase (PI3K) family of lipid kinases regulates diverse aspects of lymphocyte behavior. This review discusses how genetic and pharmacological tools have yielded an increasingly detailed understanding of how PI3K enzymes function at different stages of lymphocyte development and activation. Following antigen receptor engagement, activated PI3K generates 3-phosphorylated inositol lipid products that serve as membrane targeting signals for numerous proteins involved in the assembly of multiprotein complexes, termed signalosomes, and immune synapse formation. In B cells, class IA PI3K is the dominant subgroup whose loss causes profound defects in development and antigen responsiveness. In T cells, both class IA and IB PI3K contribute to development and immune function. PI3K also regulates both chemokine responsiveness and antigen-driven changes in lymphocyte trafficking. PI3K modulates the function not only of effector T cells, but also regulatory T cells; these disparate functions culminate in unexpected autoimmune phenotypes in mice with PI3K-deficient T cells. Thus, PI3K signaling is not a simple switch to promote cellular activation, but rather an intricate web of interactions that must be properly balanced to ensure appropriate cellular responses and maintain immune homeostasis. Defining these complexities remains a challenge for pharmaceutical development of PI3K inhibitors to combat inflammation and autoimmunity.
Collapse
Affiliation(s)
- David A Fruman
- Department of Molecular Biology and Biochemistry, and Center for Immunology, University of California at Irvine, Irvine, CA, USA.
| | | |
Collapse
|
5
|
Hawkins ED, Russell SM. Upsides and downsides to polarity and asymmetric cell division in leukemia. Oncogene 2009; 27:7003-17. [PMID: 19029941 DOI: 10.1038/onc.2008.350] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The notion that polarity regulators can act as tumor suppressors in epithelial cells is now well accepted. The function of these proteins in lymphocytes is less well explored, and their possible function as suppressors of leukemia has had little attention so far. We review the literature on lymphocyte polarity and the growing recognition that polarity proteins have an important function in lymphocyte function. We then describe molecular relationships between the polarity network and signaling pathways that have been implicated in leukemogenesis, which suggest mechanisms by which the polarity network might impact on leukemogenesis. We particularly focus on the possibility that disruption of polarity might alter asymmetric cell division (ACD), and that this might be a leukemia-initiating event. We also explore the converse possibility that leukemic stem cells might be produced or maintained by ACD, and therefore that Dlg, Scribble and Lgl might be important regulators of this process.
Collapse
Affiliation(s)
- E D Hawkins
- Immune Signalling Laboratory, Cancer Immunology, Research Division, Peter MacCallum Cancer Centre, East Melbourne, Victoria, Australia
| | | |
Collapse
|
6
|
Sumen C, Dustin ML, Davis MM. T cell receptor antagonism interferes with MHC clustering and integrin patterning during immunological synapse formation. ACTA ACUST UNITED AC 2004; 166:579-90. [PMID: 15314068 PMCID: PMC2172210 DOI: 10.1083/jcb.200404059] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
T cell activation by nonself peptide–major histocompatibility complex (MHC) antigenic complexes can be blocked by particular sequence variants in a process termed T cell receptor antagonism. The inhibition mechanism is not understood, although such variants are encountered in viral infections and may aid immune evasion. Here, we study the effect of antagonist peptides on immunological synapse formation by T cells. This cellular communication process features early integrin engagement and T cell motility arrest, referred to as the “stop signal.” We find that synapses formed on membranes presenting antagonist–agonist complexes display reduced MHC density, which leads to reduced T cell proliferation that is not overcome by the costimulatory ligands CD48 and B7-1. Most T cells fail to arrest and crawl slowly with a dense ICAM-1 crescent at the leading edge. Similar aberrant patterns of LFA-1/ICAM-1 engagement in live T–B couples correlate with reduced calcium flux and IL-2 secretion. Hence, antagonist peptides selectively disable MHC clustering and the stop signal, whereas LFA-1 valency up-regulation occurs normally.
Collapse
Affiliation(s)
- Cenk Sumen
- Howard Hughes Medical Institute, Stanford University School of Medicine, Stanford, CA, USA
| | | | | |
Collapse
|
7
|
Spitaler M, Cantrell DA. Protein kinase C and beyond. Nat Immunol 2004; 5:785-90. [PMID: 15282562 DOI: 10.1038/ni1097] [Citation(s) in RCA: 222] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2004] [Accepted: 06/07/2004] [Indexed: 11/08/2022]
Abstract
Protein kinase C molecules regulate both positive and negative signal transduction pathways essential for the initiation and homeostasis of immune responses. There are multiple isoforms of protein kinase C that are activated differently by calcium and diacylglycerol, and these are activated mainly by antigen receptors in T cells, B cells and mast cells. Additionally, mammals express several other diacylglycerol binding proteins that are linked to a network of key signal transduction pathways that control lymphocyte biology. Diacylglycerol and protein kinase C regulate a broad range of gene transcription programs but also modulate integrins, chemokine responses and antigen receptors, thereby regulating lymphocyte adhesion, migration, differentiation and proliferation.
Collapse
Affiliation(s)
- Martin Spitaler
- School of Life Sciences, Division of Cell Biology & Immunology, University of Dundee, MSI/WTB Complex, Dow Street, Dundee DD1 5EH, UK
| | | |
Collapse
|