1
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Hernández-Barranco A, Santos V, Mazariegos MS, Caleiras E, Nogués L, Mourcin F, Léonard S, Oblet C, Genebrier S, Rossille D, Benguría A, Sanz A, Vázquez E, Dopazo A, Efeyan A, Ortega-Molina A, Cogne M, Tarte K, Peinado H. NGFR regulates stromal cell activation in germinal centers. Cell Rep 2024; 43:113705. [PMID: 38307025 DOI: 10.1016/j.celrep.2024.113705] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Revised: 11/30/2023] [Accepted: 01/09/2024] [Indexed: 02/04/2024] Open
Abstract
Nerve growth factor receptor (NGFR) is expressed by follicular dendritic cells (FDCs). However, the role of NGFR in the humoral response is not well defined. Here, we study the effect of Ngfr loss on lymph node organization and function, demonstrating that Ngfr depletion leads to spontaneous germinal center (GC) formation and an expansion of the GC B cell compartment. In accordance with this effect, stromal cells are altered in Ngfr-/- mice with a higher frequency of FDCs, characterized by CD21/35, MAdCAM-1, and VCAM-1 overexpression. GCs are located ectopically in Ngfr-/- mice, with lost polarization together with impaired high-affinity antibody production and an increase in circulating autoantibodies. We observe higher levels of autoantibodies in Bcl2 Tg/Ngfr-/- mice, concomitant with a higher incidence of autoimmunity and lower overall survival. Our work shows that NGFR is involved in maintaining GC structure and function, participating in GC activation, antibody production, and immune tolerance.
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Affiliation(s)
- Alberto Hernández-Barranco
- Microenvironment and Metastasis Laboratory, Molecular Oncology Program, Spanish National Cancer Research Center (CNIO), 28029 Madrid, Spain
| | - Vanesa Santos
- Microenvironment and Metastasis Laboratory, Molecular Oncology Program, Spanish National Cancer Research Center (CNIO), 28029 Madrid, Spain
| | - Marina S Mazariegos
- Microenvironment and Metastasis Laboratory, Molecular Oncology Program, Spanish National Cancer Research Center (CNIO), 28029 Madrid, Spain; Liver Injury and Inflammation Laboratory, Department of Immunology, Ophthalmology and ENT, School of Medicine, Complutense University, 28040 Madrid, Spain
| | - Eduardo Caleiras
- Histopathology Unit, Biotechnology Program, Spanish National Cancer Research Center (CNIO), 28029 Madrid, Spain
| | - Laura Nogués
- Microenvironment and Metastasis Laboratory, Molecular Oncology Program, Spanish National Cancer Research Center (CNIO), 28029 Madrid, Spain
| | - Frédéric Mourcin
- UMR U1236, University Rennes, INSERM, EFS Bretagne, Equipe Labellisée Ligue Contre le Cancer, 35000 Rennes, France
| | - Simon Léonard
- UMR U1236, University Rennes, INSERM, EFS Bretagne, Equipe Labellisée Ligue Contre le Cancer, 35000 Rennes, France
| | - Christelle Oblet
- Immunology Department, Faculty of Medicine, Limoges University, CNRS Umr 7276, Inserm U1262, 87000 Limoges, France
| | - Steve Genebrier
- UMR U1236, University Rennes, INSERM, EFS Bretagne, Equipe Labellisée Ligue Contre le Cancer, 35000 Rennes, France
| | - Delphine Rossille
- UMR U1236, University Rennes, INSERM, EFS Bretagne, Equipe Labellisée Ligue Contre le Cancer, 35000 Rennes, France; SITI Lab, Pôle Biologie, CHU Rennes, 35000 Rennes, France
| | - Alberto Benguría
- Genomic Unit, Spanish National Cardiovascular Research, Carlos III, 28029 Madrid, Spain
| | - Alba Sanz
- Metabolism and Cell Signaling Laboratory, Molecular Oncology Program, Spanish National Cancer Research Centre (CNIO), 28029 Madrid, Spain
| | - Enrique Vázquez
- Genomic Unit, Spanish National Cardiovascular Research, Carlos III, 28029 Madrid, Spain
| | - Ana Dopazo
- Genomic Unit, Spanish National Cardiovascular Research, Carlos III, 28029 Madrid, Spain
| | - Alejo Efeyan
- Metabolism and Cell Signaling Laboratory, Molecular Oncology Program, Spanish National Cancer Research Centre (CNIO), 28029 Madrid, Spain
| | - Ana Ortega-Molina
- Metabolism and Cell Signaling Laboratory, Molecular Oncology Program, Spanish National Cancer Research Centre (CNIO), 28029 Madrid, Spain; Metabolism in Cancer and Ageing Laboratory, Immune System and Function Department, Centro de Biología Molecular "Severo Ochoa" (CMBSO-CSIC), Madrid 28049, Spain
| | - Michel Cogne
- UMR U1236, University Rennes, INSERM, EFS Bretagne, Equipe Labellisée Ligue Contre le Cancer, 35000 Rennes, France
| | - Karin Tarte
- UMR U1236, University Rennes, INSERM, EFS Bretagne, Equipe Labellisée Ligue Contre le Cancer, 35000 Rennes, France; SITI Lab, Pôle Biologie, CHU Rennes, 35000 Rennes, France
| | - Héctor Peinado
- Microenvironment and Metastasis Laboratory, Molecular Oncology Program, Spanish National Cancer Research Center (CNIO), 28029 Madrid, Spain.
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2
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Oyler BL, Valencia-Dávila JA, Moysi E, Molyvdas A, Ioannidou K, March K, Ambrozak D, De Leval L, Fabozzi G, Woods AS, Koup RA, Petrovas C. Multilevel human secondary lymphoid immune system compartmentalization revealed by complementary imaging approaches. iScience 2023; 26:107261. [PMID: 37520703 PMCID: PMC10371825 DOI: 10.1016/j.isci.2023.107261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Revised: 04/12/2023] [Accepted: 06/27/2023] [Indexed: 08/01/2023] Open
Abstract
Secondary human lymphoid tissue immune reactions take place in a highly coordinated environment with compartmentalization representing a fundamental feature of this organization. In situ profiling methodologies are indispensable for the understanding of this compartmentalization. Here, we propose a complementary experimental approach aiming to reveal different aspects of this process. The analysis of human tonsils, using a combination of single cell phenotypic analysis based on flow cytometry and multiplex imaging and mass spectrometry-based methodologies, revealed a compartmentalized organization at the cellular and molecular levels. More specifically, the skewed distribution of highly specialized immune cell subsets and relevant soluble mediators was accompanied by a compartmentalized localization of several lipids across different anatomical areas of the tonsillar tissue. The performance of such combinatorial experimental approaches could lead to the identification of novel in situ interactions and molecular targets for the in vivo manipulation of lymphoid organ, particularly the germinal center, immune reactions.
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Affiliation(s)
- Benjamin L. Oyler
- Tissue Analysis Core, Immunology Laboratory, Vaccine Research Center, NIAID, NIH, Bethesda, MD, USA
| | | | - Eirini Moysi
- Tissue Analysis Core, Immunology Laboratory, Vaccine Research Center, NIAID, NIH, Bethesda, MD, USA
| | - Adam Molyvdas
- Tissue Analysis Core, Immunology Laboratory, Vaccine Research Center, NIAID, NIH, Bethesda, MD, USA
| | - Kalliopi Ioannidou
- Department of Laboratory Medicine and Pathology, Institute of Pathology, Lausanne University Hospital and Lausanne University, Lausanne, Switzerland
| | - Kylie March
- Tissue Analysis Core, Immunology Laboratory, Vaccine Research Center, NIAID, NIH, Bethesda, MD, USA
| | - David Ambrozak
- Tissue Analysis Core, Immunology Laboratory, Vaccine Research Center, NIAID, NIH, Bethesda, MD, USA
| | - Laurence De Leval
- Department of Laboratory Medicine and Pathology, Institute of Pathology, Lausanne University Hospital and Lausanne University, Lausanne, Switzerland
| | - Giulia Fabozzi
- Tissue Analysis Core, Immunology Laboratory, Vaccine Research Center, NIAID, NIH, Bethesda, MD, USA
| | - Amina S. Woods
- Tissue Analysis Core, Immunology Laboratory, Vaccine Research Center, NIAID, NIH, Bethesda, MD, USA
| | - Richard A. Koup
- Tissue Analysis Core, Immunology Laboratory, Vaccine Research Center, NIAID, NIH, Bethesda, MD, USA
| | - Constantinos Petrovas
- Tissue Analysis Core, Immunology Laboratory, Vaccine Research Center, NIAID, NIH, Bethesda, MD, USA
- Department of Laboratory Medicine and Pathology, Institute of Pathology, Lausanne University Hospital and Lausanne University, Lausanne, Switzerland
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3
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Akama-Garren EH, Carroll MC. T Cell Help in the Autoreactive Germinal Center. Scand J Immunol 2022; 95:e13192. [PMID: 35587582 DOI: 10.1111/sji.13192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2022] [Revised: 05/10/2022] [Accepted: 05/13/2022] [Indexed: 11/29/2022]
Abstract
The germinal center serves as a site of B cell selection and affinity maturation, critical processes for productive adaptive immunity. In autoimmune disease tolerance is broken in the germinal center reaction, leading to production of autoreactive B cells that may propagate disease. Follicular T cells are crucial regulators of this process, providing signals necessary for B cell survival in the germinal center. Here we review the emerging roles of follicular T cells in the autoreactive germinal center. Recent advances in immunological techniques have allowed study of the gene expression profiles and repertoire of follicular T cells at unprecedented resolution. These studies provide insight into the potential role follicular T cells play in preventing or facilitating germinal center loss of tolerance. Improved understanding of the mechanisms of T cell help in autoreactive germinal centers provides novel therapeutic targets for diseases of germinal center dysfunction.
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Affiliation(s)
- Elliot H Akama-Garren
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA.,Harvard-MIT Health Sciences and Technology, Harvard Medical School, Boston, MA, USA
| | - Michael C Carroll
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
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4
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Haberman AM, Gonzalez DG, Wong P, Zhang TT, Kerfoot SM. Germinal center B cell initiation, GC maturation, and the coevolution of its stromal cell niches. Immunol Rev 2019; 288:10-27. [PMID: 30874342 DOI: 10.1111/imr.12731] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Accepted: 11/28/2018] [Indexed: 12/13/2022]
Abstract
Throughout the developing GC response, B cell survival and fate choices made at the single cell level are dependent on signals received largely through interactions with other cells, often with cognate T cells. The type of signals that a given B cell can encounter is dictated by its location within tissue microarchitecture. The focus of this review is on the initiation and evolution of the GC response at the earliest time points. Here, we review the key factors influencing the progression of GC B cell differentiation that are both stage and context dependent. Finally, we describe the coevolution of niches within and surrounding the GC that influence the outcome of the GC response.
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Affiliation(s)
- Ann M Haberman
- Department of Immunobiology, Yale University, New Haven, Connecticut.,Department of Laboratory Medicine, Yale University, New Haven, Connecticut
| | - David G Gonzalez
- Department of Immunobiology, Yale University, New Haven, Connecticut.,Department of Genetics, Yale University, New Haven, Connecticut
| | - Patrick Wong
- Department of Immunobiology, Yale University, New Haven, Connecticut
| | - Ting-Ting Zhang
- Department of Immunobiology, Yale University, New Haven, Connecticut
| | - Steven M Kerfoot
- Department of Microbiology and Immunology, Western University, London, ON, Canada
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5
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Reboldi A, Cyster JG. Peyer's patches: organizing B-cell responses at the intestinal frontier. Immunol Rev 2016; 271:230-45. [PMID: 27088918 DOI: 10.1111/imr.12400] [Citation(s) in RCA: 198] [Impact Index Per Article: 24.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Secondary lymphoid tissues share the important function of bringing together antigens and rare antigen-specific lymphocytes to foster induction of adaptive immune responses. Peyer's patches (PPs) are unique compared to other secondary lymphoid tissues in their continual exposure to an enormous diversity of microbiome- and food-derived antigens and in the types of pathogens they encounter. Antigens are delivered to PPs by specialized microfold (M) epithelial cells and they may be captured and presented by resident dendritic cells (DCs). In accord with their state of chronic microbial antigen exposure, PPs exhibit continual germinal center (GC) activity. These GCs not only contribute to the generation of B cells and plasma cells producing somatically mutated gut antigen-specific IgA antibodies but have also been suggested to support non-specific antigen diversification of the B-cell repertoire. Here, we review current understanding of how PPs foster B-cell encounters with antigen, how they favor isotype switching to the secretory IgA isotype, and how their GC responses may uniquely contribute to mucosal immunity.
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Affiliation(s)
- Andrea Reboldi
- Howard Hughes Medical Institute and Department of Microbiology and Immunology, University of California San Francisco, San Francisco, CA, USA
| | - Jason G Cyster
- Howard Hughes Medical Institute and Department of Microbiology and Immunology, University of California San Francisco, San Francisco, CA, USA
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6
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Balogh P, Horváth G, Szakal AK. Immunoarchitecture of Distinct Reticular Fibroblastic Domains in the White Pulp of Mouse Spleen. J Histochem Cytochem 2016; 52:1287-98. [PMID: 15385575 DOI: 10.1177/002215540405201005] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
The development of peripheral lymphoid tissues requires a series of cognate interactions between hemopoietic and stromal cell populations, including reticular fibroblasts, which form the mesenchymal scaffolding of distinct tissue compartments. Here we describe the formation of different fibroblastic domains in the mouse spleen white pulp by using two new rat monoclonal antibodies (MAbs). In the white pulp, MAb IBL-10 labels both T- and B-cell zone reticular elements at various intensities. The IBL-10hi subset was found primarily at the edge between the peripheral part of the PALS and follicles, and the IBL-10lo compartment was distributed evenly within the white pulp. The IBL-10hi subset appeared during the first 2 postnatal weeks and was absent in SCID mice. The white pulp fibroblast subset identified with MAb IBL-11 had a different tissue distribution and kinetics of ontogeny, with an appearance overwhelmingly restricted to the PALS and a narrow rim at the edge of the follicular border area toward the marginal zone. The appearance of IBL-11–positive reticular cells was delayed compared with that of the IBL-10lo–positive subset. The formation was independent of the influence of antigen receptor–bearing lymphocytes, as evidenced by the presence of IBL-11–positive fibroblasts in SCID mice. By transferring various lymphocyte subsets into SCID mice, partial compartmentalization of the white pulp fibroblasts could be induced, indicating that these mesenchymal fibroblast precursors retain their ability to differentiate upon encountering mature T- or B-cells.
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Affiliation(s)
- Péter Balogh
- Department of Immunology, University of Pécs, Szigeti út 12, 7643 Pécs, Hungary.
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7
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Wang X, Rodda LB, Bannard O, Cyster JG. Integrin-mediated interactions between B cells and follicular dendritic cells influence germinal center B cell fitness. THE JOURNAL OF IMMUNOLOGY 2014; 192:4601-9. [PMID: 24740506 DOI: 10.4049/jimmunol.1400090] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Integrin-ligand interactions between germinal center (GC) B cells and Ag-presenting follicular dendritic cells (FDCs) have been suggested to play central roles during GC responses, but their in vivo requirement has not been directly tested. In this study, we show that, whereas integrins αLβ2 and α4β1 are highly expressed and functional on mouse GC B cells, removal of single integrins or their ligands had little effect on B cell participation in the GC response. Combined β2 integrin deficiency and α4 integrin blockade also did not affect the GC response against a particulate Ag. However, the combined integrin deficiency did cause B cells to be outcompeted in splenic GC responses against a soluble protein Ag and in mesenteric lymph node GC responses against gut-derived Ags. Similar findings were made for β2-deficient B cells in mice lacking VCAM1 on FDCs. The reduced fitness of the GC B cells did not appear to be due to decreased Ag acquisition, proliferation rates, or pAKT levels. In summary, our findings provide evidence that αLβ2 and α4β1 play overlapping and context-dependent roles in supporting interactions with FDCs that can augment the fitness of responding GC B cells. We also find that mouse GC B cells upregulate αvβ3 and adhere to vitronectin and milk-fat globule epidermal growth factor VIII protein. Integrin β3-deficient B cells contributed in a slightly exaggerated manner to GC responses, suggesting this integrin has a regulatory function in GC B cells.
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Affiliation(s)
- Xiaoming Wang
- Howard Hughes Medical Institute, University of California San Francisco, San Francisco, CA 94143
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8
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Myers RC, King RG, Carter RH, Justement LB. Lymphotoxin α1β2 expression on B cells is required for follicular dendritic cell activation during the germinal center response. Eur J Immunol 2013; 43:348-59. [PMID: 23112125 PMCID: PMC3753018 DOI: 10.1002/eji.201242471] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2012] [Revised: 09/26/2012] [Accepted: 10/23/2012] [Indexed: 11/10/2022]
Abstract
CD19-deficient mice were used as a model to study follicular dendritic cell (FDC) activation because these mice have normal numbers of FDC-containing primary follicles, but lack the ability to activate FDCs or form GCs. It was hypothesized that CD19 expression is necessary for B-cell activation and upregulation of membrane lymphotoxin (mLT) expression, which promotes FDC activation. Using VCAM-1 and FcγRII/III as FDC activation markers, it was determined that the adoptive transfer of CD19(+) wild-type B cells into CD19-deficient hosts rescued GC formation and FDC activation, demonstrating that CD19 expression on B cells is required for FDC activation. In contrast, CD19(+) donor B cells lacking mLT were unable to induce VCAM-1 expression on FDCs, furthermore FcγRII/III upregulation was impaired in FDCs stimulated with mLT-deficient B cells. VCAM-1 expression on FDCs, but not FcγRII/III, was rescued when CD19-deficient B cells expressing transgenic mLT were cotransferred into recipient mice with CD19(+) , mLT-deficient B cells, suggesting that FDC activation requires the CD19-dependent upregulation of mLT on activated B cells. Collectively, these data demonstrate that activated B cells are responsible for the initiation of FDC activation resulting in a microenvironment supportive of GC development and maintenance.
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MESH Headings
- Animals
- Antigens, CD19/biosynthesis
- Antigens, CD19/genetics
- Antigens, CD19/immunology
- B-Lymphocytes/immunology
- B-Lymphocytes/metabolism
- Dendritic Cells, Follicular/immunology
- Dendritic Cells, Follicular/metabolism
- Germinal Center/immunology
- Germinal Center/metabolism
- Lymphocyte Activation
- Lymphotoxin alpha1, beta2 Heterotrimer/biosynthesis
- Lymphotoxin alpha1, beta2 Heterotrimer/genetics
- Lymphotoxin alpha1, beta2 Heterotrimer/immunology
- Mice
- Mice, Inbred C57BL
- Receptors, IgG/biosynthesis
- Receptors, IgG/genetics
- Receptors, IgG/immunology
- Up-Regulation
- Vascular Cell Adhesion Molecule-1/biosynthesis
- Vascular Cell Adhesion Molecule-1/genetics
- Vascular Cell Adhesion Molecule-1/immunology
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Affiliation(s)
- Riley C. Myers
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL 35294
| | - R. Glenn King
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Robert H. Carter
- National Institute of Arthritis and Musculoskeletal and Skin Diseases, Bethesda, MD 20892
| | - Louis B. Justement
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL 35294
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9
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Cook-Mills JM, Marchese ME, Abdala-Valencia H. Vascular cell adhesion molecule-1 expression and signaling during disease: regulation by reactive oxygen species and antioxidants. Antioxid Redox Signal 2011; 15:1607-38. [PMID: 21050132 PMCID: PMC3151426 DOI: 10.1089/ars.2010.3522] [Citation(s) in RCA: 367] [Impact Index Per Article: 28.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The endothelium is immunoregulatory in that inhibiting the function of vascular adhesion molecules blocks leukocyte recruitment and thus tissue inflammation. The function of endothelial cells during leukocyte recruitment is regulated by reactive oxygen species (ROS) and antioxidants. In inflammatory sites and lymph nodes, the endothelium is stimulated to express adhesion molecules that mediate leukocyte binding. Upon leukocyte binding, these adhesion molecules activate endothelial cell signal transduction that then alters endothelial cell shape for the opening of passageways through which leukocytes can migrate. If the stimulation of this opening is blocked, inflammation is blocked. In this review, we focus on the endothelial cell adhesion molecule, vascular cell adhesion molecule-1 (VCAM-1). Expression of VCAM-1 is induced on endothelial cells during inflammatory diseases by several mediators, including ROS. Then, VCAM-1 on the endothelium functions as both a scaffold for leukocyte migration and a trigger of endothelial signaling through NADPH oxidase-generated ROS. These ROS induce signals for the opening of intercellular passageways through which leukocytes migrate. In several inflammatory diseases, inflammation is blocked by inhibition of leukocyte binding to VCAM-1 or by inhibition of VCAM-1 signal transduction. VCAM-1 signal transduction and VCAM-1-dependent inflammation are blocked by antioxidants. Thus, VCAM-1 signaling is a target for intervention by pharmacological agents and by antioxidants during inflammatory diseases. This review discusses ROS and antioxidant functions during activation of VCAM-1 expression and VCAM-1 signaling in inflammatory diseases.
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Affiliation(s)
- Joan M Cook-Mills
- Allergy-Immunology Division, Northwestern University Feinberg School of Medicine, 240 E Huron, Chicago, IL 60611, USA.
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10
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Takakura I, Miyazawa K, Kanaya T, Itani W, Watanabe K, Ohwada S, Watanabe H, Hondo T, Rose MT, Mori T, Sakaguchi S, Nishida N, Katamine S, Yamaguchi T, Aso H. Orally administered prion protein is incorporated by m cells and spreads into lymphoid tissues with macrophages in prion protein knockout mice. THE AMERICAN JOURNAL OF PATHOLOGY 2011; 179:1301-9. [PMID: 21763679 DOI: 10.1016/j.ajpath.2011.05.058] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2010] [Revised: 05/13/2011] [Accepted: 05/23/2011] [Indexed: 12/21/2022]
Abstract
Transmissible spongiform encephalopathies are fatal neurodegenerative diseases. Infection by the oral route is assumed to be important, although its pathogenesis is not understood. Using prion protein (PrP) knockout mice, we investigated the sequence of events during the invasion of orally administered PrPs through the intestinal mucosa and the spread into lymphoid tissues and the peripheral nervous system. Orally administered PrPs were incorporated by intestinal epitheliocytes in the follicle-associated epithelium and villi within 1 hour. PrP-positive cells accumulated in the subfollicle region of Peyer's patches a few hours thereafter. PrP-positive cells spread toward the mesenteric lymph nodes and spleen after the accumulation of PrPs in the Peyer's patches. The number of PrP molecules in the mesenteric lymph nodes and spleen peaked at 2 days and 6 days after inoculation, respectively. The epitheliocytes in the follicle-associated epithelium incorporating PrPs were annexin V-positive microfold cells and PrP-positive cells in Peyer's patches and spleen were CD11b-positive and CD14-positive macrophages. Additionally, PrP-positive cells in Peyer's patches and spleen were detected in the vicinity of peripheral nerve fibers in the early stages of infection. These results indicate that orally delivered PrPs were incorporated by microfold cells promptly after challenge and that macrophages might act as a transporter of incorporated PrPs from the Peyer's patches to other lymphoid tissues and the peripheral nervous system.
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Affiliation(s)
- Ikuro Takakura
- Cellular Biology Laboratory, Graduate School of Agricultural Science, Tohoku University, Sendai, Japan
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11
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Fritz JH, Gommerman JL. Cytokine/stromal cell networks and lymphoid tissue environments. J Interferon Cytokine Res 2010; 31:277-89. [PMID: 21133813 DOI: 10.1089/jir.2010.0121] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Initiation of an effective adaptive immune response against a foreign pathogen requires orchestrated encounters between lymphocytes and antigen-presenting cells. The tissues of the lymphoid system provide the ideal environment for increasing the efficiency of these encounters. Within the spleen, the mucosal-associated lymphoid tissues, and the lymph nodes, an intricate network of stromal cells, collagen fibers, and extracellular matrix exists that effectively compartmentalizes immune cells as they transit through these tissues. The stromal cells within lymphoid tissues are by no means homogenous, and it is now clear that these cells are not merely sessile bystanders during immune responses. Indeed, stromal cells within lymphoid tissues are the source of important cytokines and chemokines that guide and polarize immune cells. Here, we review the cytokines that maintain the integrity of this important stromal scaffold system within the lymphoid tissue, paying particular attention to the Lymphotoxin pathway, which is an important player in stromal cell biology. How cytokines maintain the organization of lymphoid tissues during development, in the adult animal, during inflammation and during disease will be discussed in sequence, and the clinical implications of targeting cytokines that regulate lymphoid tissue stroma will be considered.
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Affiliation(s)
- Jörg H Fritz
- Department of Immunology, University of Toronto , Toronto, Ontario, Canada
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12
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Hall LJ, Clare S, Dougan G. Probing local innate immune responses after mucosal immunisation. JOURNAL OF IMMUNE BASED THERAPIES AND VACCINES 2010; 8:5. [PMID: 20836885 PMCID: PMC2945349 DOI: 10.1186/1476-8518-8-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/01/2010] [Accepted: 09/13/2010] [Indexed: 11/10/2022]
Abstract
Background Intranasal immunisation is potentially a very effective route for inducing both mucosal and systemic immunity to an infectious agent. Methods Balb/c mice were intranasally immunised with the mucosal adjuvant heat labile toxin and the Mycobacterium tuberculosis fusion protein Ag85B-ESAT6 and early changes in innate immune responses within local mucosal tissues were examined using flow cytometry and confocal microscopy. Antigen-specific humoral and cellular immune responses were also evaluated. Results Intranasal immunisation induced significant changes in both number and distribution of dendritic cells, macrophages and neutrophils within the nasal-associated lymphoid tissue and cervical lymph nodes in comparison to controls as early as 5 h post immunisation. Immunisation also resulted in a rapid and transient increase in activation marker expression first in the nasal-associated lymphoid tissue, and then in the cervical lymph nodes. This heightened activation status was also apparent from the pro-inflammatory cytokine profiles of these innate populations. In addition we also showed increased expression and distribution of a number of different cell adhesion molecules early after intranasal immunisation within these lymphoid tissues. These observed early changes correlated with the induction of a TH1 type immune response. Conclusions These data provide insights into the complex nature of innate immune responses induced following intranasal immunisation within the upper respiratory tract, and may help clarify the concepts and provide the tools that are needed to exploit the full potential of mucosal vaccines.
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Affiliation(s)
- Lindsay J Hall
- Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridgeshire, CB10 1SA, UK.
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13
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Hauser AE, Kerfoot SM, Haberman AM. Cellular choreography in the germinal center: new visions from in vivo imaging. Semin Immunopathol 2010; 32:239-55. [PMID: 20614218 DOI: 10.1007/s00281-010-0214-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2010] [Accepted: 06/22/2010] [Indexed: 11/25/2022]
Abstract
Germinal centers (GC) are large aggregates of proliferating B lymphocytes within follicles of lymphoid tissue that form during adaptive immune responses. GCs are the source of long-lived B cells that form the basis for pathogen-specific lifelong B cell immunity. The complex architecture of these structures includes subdomains that differ significantly in their stromal cell and T lymphocyte subset composition. In part due to their structural complexity and potential to generate some lymphomas, much interest and many theories about GC dynamics have emerged. Here, we review recent research employing in vivo imaging that has begun to untangle some of the mysteries.
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Affiliation(s)
- Anja E Hauser
- Deutsches Rheuma-Forschungszentrum (DRFZ), Berlin 10117, Germany
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14
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Qi CF, Li Z, Raffeld M, Wang H, Kovalchuk AL, Morse HC. Differential expression of IRF8 in subsets of macrophages and dendritic cells and effects of IRF8 deficiency on splenic B cell and macrophage compartments. Immunol Res 2010; 45:62-74. [PMID: 18663414 DOI: 10.1007/s12026-008-8032-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
IRF8, a transcription factor restricted primarily to hematopoietic cells, is known to influence the differentiation and function of dendritic cells (DC), macrophages, granulocytes and B cells. In human tonsil, IRF8 is expressed at high levels by intrafollicular macrophages and DC, but at much lower levels by tingible body macrophages in germinal centers (GCs) and little, if at all, by follicular DC. Spleens of IRF8-deficient mice had reduced numbers of white pulp follicles and GCs that were irregular in shape. The frequency of follicular B cells was significantly reduced while the population of marginal zone (MZ) B cells was increased. In addition, MZ macrophages were reduced in number and abnormally distributed, while metallophilic macrophages were normal. These findings demonstrate differential requirements for IRF8 among distinct subsets of B cells, DC, and macrophages.
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Affiliation(s)
- Chen-Feng Qi
- Laboratory of Immunopathology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 5640 Fishers Lane, Twinbrook I, Room 1528, Rockville, MD 20852, USA.
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15
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El Shikh MEM, El Sayed RM, Sukumar S, Szakal AK, Tew JG. Activation of B cells by antigens on follicular dendritic cells. Trends Immunol 2010; 31:205-11. [PMID: 20418164 DOI: 10.1016/j.it.2010.03.002] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2009] [Revised: 02/01/2010] [Accepted: 03/25/2010] [Indexed: 12/13/2022]
Abstract
A need for antigen-processing and presentation to B cells is not widely appreciated. However, cross-linking of multiple B cell receptors (BCRs) by T-independent antigens delivers a potent signal that induces antibody responses. Such BCR cross-linking also occurs in germinal centers where follicular dendritic cells (FDCs) present multimerized antigens as periodically arranged antigen-antibody complexes (ICs). Unlike T cells that recognize antigens as peptide-MHC complexes, optimal B cell-responses are induced by multimerized FDC-ICs that simultaneously engage multiple BCRs. FDC-FcgammaRIIB mediates IC-periodicity and FDC-BAFF, FDC-IL-6 and FDC-C4bBP are co-stimulators. Remarkably, specific antibody responses can be induced by FDC-ICs in the absence of T cells, opening up the exciting possibility that people with T cell insufficiencies may be immunized with T-dependent vaccines via FDC-ICs.
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Affiliation(s)
- Mohey Eldin M El Shikh
- Department of Microbiology and Immunology, Virginia Commonwealth University, PO Box 980678, Richmond, VA 23298-0678, USA
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16
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17
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Allen CDC, Cyster JG. Follicular dendritic cell networks of primary follicles and germinal centers: phenotype and function. Semin Immunol 2008; 20:14-25. [PMID: 18261920 DOI: 10.1016/j.smim.2007.12.001] [Citation(s) in RCA: 310] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2007] [Accepted: 12/06/2007] [Indexed: 12/11/2022]
Abstract
Follicular dendritic cells (FDCs) were identified decades ago by their ability to retain immune complexes and more recent findings indicate that they are a source of B cell attractants and trophic factors. New imaging studies have shown that B cells closely associate with their dendritic processes during migration. Here we will review the properties of these specialized follicular stromal cells and provide an update on the requirements for their maturation into phenotypically distinct cells within germinal center light and dark zones. We will then discuss current understanding of how they help support the B cell immune response.
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Affiliation(s)
- Christopher D C Allen
- Howard Hughes Medical Institute and Department of Microbiology and Immunology, 513 Parnassus Avenue, Box 0414, University of California, San Francisco, CA 94143-0414, USA.
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18
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Allen CDC, Okada T, Cyster JG. Germinal-center organization and cellular dynamics. Immunity 2007; 27:190-202. [PMID: 17723214 PMCID: PMC2242846 DOI: 10.1016/j.immuni.2007.07.009] [Citation(s) in RCA: 686] [Impact Index Per Article: 40.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2007] [Accepted: 07/02/2007] [Indexed: 12/27/2022]
Abstract
Germinal centers (GCs) are important sites of antibody affinity maturation. In the classical model, the GC dark zone contains large centroblasts that are rapidly proliferating and undergoing somatic hypermutation of their antibody variable-region genes. Centroblasts give rise to smaller nonproliferating centrocytes in the light zone that compete for binding antigen on follicular dendritic cells. Recently, the approach of real-time imaging of GCs by two-photon microscopy of intact lymph nodes has provided new insights into GC dynamics that both support and challenge fundamental aspects of this model. Here we review recent and older findings on cell migration, proliferation, and interaction dynamics in the GC and discuss a model in which dark- and light-zone cells are morphologically similar, proliferation occurs in both zones, and GC B cells compete for T cell help as well as antigen.
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Affiliation(s)
- Christopher D C Allen
- Howard Hughes Medical Institute, Department of Microbiology and Immunology, University of California, San Francisco, CA 94143-0414, USA.
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19
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El Shikh MEM, El Sayed RM, Wu Y, Szakal AK, Tew JG. TLR4 on Follicular Dendritic Cells: An Activation Pathway That Promotes Accessory Activity. THE JOURNAL OF IMMUNOLOGY 2007; 179:4444-50. [PMID: 17878340 DOI: 10.4049/jimmunol.179.7.4444] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Microbial molecular patterns engage TLRs and activate dendritic cells and other accessory cells. Follicular dendritic cells (FDCs) exist in resting and activated states, but are activated in germinal centers, where they provide accessory function. We reasoned that FDCs might express TLRs and that engagement might activate FDCs by up-regulating molecules important for accessory activity. To test this hypothesis, TLR4 expression on FDCs was studied in situ with immunohistochemistry, followed by flow cytometry and RT-PCR analysis. TLR4 was expressed on FDC reticula in situ, and flow cytometry indicated that TLR4 was expressed on surface membranes and TLR4 message was readily apparent in FDCs by RT-PCR. Injecting mice or treating purified FDCs with LPS up-regulated molecules important for accessory activity including, FDC-Fc gammaRIIB, FDC-ICAM-1, and FDC-VCAM-1. Treatment of purified FDCs with LPS also induced intracellular phospho-IkappaB-alpha, indicating NF-kappaB activation, and that correlated with increased Fc gammaRIIB, ICAM-1, and VCAM-1. FDCs in C3H/HeJ mice were not activated with LPS even when mice were reconstituted with C3H/HeN leukocytes, suggesting that engagement of FDC-TLR4 is necessary for activation. Moreover, activated FDCs exhibited increased accessory activity in anti-OVA recall responses in vitro, and the FDC number could be reduced 4-fold if they were activated. In short, we report expression of TLR4 on FDCs for the first time and that engagement of FDC-TLR4 activated NF-kappaB, up-regulated expression of molecules important in FDC accessory function, including Fc gammaRIIB, ICAM-1, and VCAM-1, as well as FDC accessory activity in promoting recall IgG responses.
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20
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Deem TL, Abdala-Valencia H, Cook-Mills JM. VCAM-1 activation of endothelial cell protein tyrosine phosphatase 1B. THE JOURNAL OF IMMUNOLOGY 2007; 178:3865-73. [PMID: 17339486 PMCID: PMC2710028 DOI: 10.4049/jimmunol.178.6.3865] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Lymphocytes migrate from the blood into tissue by binding to and migrating across endothelial cells. One of the endothelial cell adhesion molecules that mediate lymphocyte binding is VCAM-1. We have reported that binding to VCAM-1 activates endothelial cell NADPH oxidase for the generation of reactive oxygen species (ROS). The ROS oxidize and stimulate an increase in protein kinase C (PKC)alpha activity. Furthermore, these signals are required for VCAM-1-dependent lymphocyte migration. In this report, we identify a role for protein tyrosine phosphatase 1B (PTP1B) in the VCAM-1 signaling pathway. In primary cultures of endothelial cells and endothelial cell lines, Ab cross-linking of VCAM-1 stimulated an increase in serine phosphorylation of PTP1B, the active form of PTP1B. Ab cross-linking of VCAM-1 also increased activity of PTP1B. This activation of PTP1B was downstream of NADPH oxidase and PKCalpha in the VCAM-1 signaling pathway as determined with pharmacological inhibitors and antisense approaches. In addition, during VCAM-1 signaling, ROS did not oxidize endothelial cell PTP1B. Instead PTP1B was activated by serine phosphorylation. Importantly, inhibition of PTP1B activity blocked VCAM-1-dependent lymphocyte migration across endothelial cells. In summary, VCAM-1 activates endothelial cell NADPH oxidase to generate ROS, resulting in oxidative activation of PKCalpha and then serine phosphorylation of PTP1B. This PTP1B activity is necessary for VCAM-1-dependent transendothelial lymphocyte migration. These data show, for the first time, a function for PTP1B in VCAM-1-dependent lymphocyte migration.
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Affiliation(s)
- Tracy L. Deem
- Department of Pathology and Laboratory Medicine, University of Cincinnati, Cincinnati, OH 45267
- Cardiovascular Research Center, University of Virginia, Charlottesville, VA 22908
| | - Hiam Abdala-Valencia
- Allergy-Immunology Division, Northwestern University, Feinberg School of Medicine, Chicago, IL 60611
- Department of Pathology and Laboratory Medicine, University of Cincinnati, Cincinnati, OH 45267
| | - Joan M. Cook-Mills
- Allergy-Immunology Division, Northwestern University, Feinberg School of Medicine, Chicago, IL 60611
- Department of Pathology and Laboratory Medicine, University of Cincinnati, Cincinnati, OH 45267
- Address correspondence and reprint requests to Dr. Joan M. Cook-Mills, Allergy-Immunology Division, Northwestern University, Feinberg School of Medicine, McGaw-304, 240 East Huron, Chicago, IL 60611. E-mail address:
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21
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Suraud V, Olivier M, Bodier CC, Guilloteau LA. Differential expression of homing receptors and vascular addressins in tonsils and draining lymph nodes: Effect of Brucella infection in sheep. Vet Immunol Immunopathol 2007; 115:239-50. [PMID: 17161868 DOI: 10.1016/j.vetimm.2006.11.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2006] [Revised: 10/18/2006] [Accepted: 11/13/2006] [Indexed: 11/24/2022]
Abstract
The differential expression of homing receptors (HR) and complementary vascular addressins was studied in T and B lymphocytes from ovine tonsils and draining lymph nodes (LN) in uninfected and Brucella melitensis-infected sheep. In uninfected sheep, CD4+CD25+ T cells expressed proportionally more L-selectin and beta1 integrin than beta7 integrin in pharyngeal and palatine tonsils and in parotid LN (PLN), retropharyngeal LN (RLN) and the peripheral prescapular LN (PSLN). In contrast, memory CD4+CD45RA- T cells expressed an equivalent proportion of the three HR in PLN and PSLN, whereas beta1 and beta7 integrins were proportionally more expressed than L-selectin in pharyngeal tonsil. beta7 integrin was proportionally more expressed than beta1 integrin or L-selectin in palatine tonsils, RLN and the mucosal mesenteric LN (MLN). beta1 integrin was proportionally more expressed in IgG+ and IgA+ cells than beta7 integrin and L-selectin in tonsils, PLN and RLN. The main endothelial addressin expressed on venules in both pharyngeal and palatine tonsils, the PLN and RLN, as well as in the PSLN, was the peripheral PNAd, while in the MLN it was MAdCAM-1. Conjunctival infection by Brucella resulted in an increase of CD4+CD25+ and CD4+CD45RA- T cell subsets, which was associated to modifications of HR expression. CD4+CD45RA- T cells expressed proportionally more beta1 and beta7 integrins than L-selectin in regional PLN and RLN, but also in PSLN. The infection induced an increase of IgG+ and IgA+ cell percentages expressing beta1 integrin in all LN, and also beta7 integrin in the RLN. PNAd continued to be expressed on venules of tonsils and draining LN after Brucella infection, and MAdCAM-1 was also weakly expressed on RLN venules. These results suggest that lymphocyte trafficking through tonsils and draining LN could involve L-selectin/PNAd interactions, as well as beta1 or beta7 integrin, possibly in interaction with VCAM-1 or MAdCAM-1. The homing of antigen-specific lymphocytes in these tissues could be modulated after conjunctival infection with Brucella, which induces the recruitment of lymphocytes that express both beta1 and/or beta7 integrin in regional and more distant LN.
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Affiliation(s)
- Vanessa Suraud
- UR 1282, Unité d'Infectiologie Animale et Santé Publique, Institut National de Recherche Agronomique, Centre de Tours-Nouzilly, F-37380 Nouzilly, France
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22
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El Shikh ME, El Sayed R, Szakal AK, Tew JG. Follicular dendritic cell (FDC)-FcgammaRIIB engagement via immune complexes induces the activated FDC phenotype associated with secondary follicle development. Eur J Immunol 2006; 36:2715-24. [PMID: 17013985 DOI: 10.1002/eji.200636122] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Follicular dendritic cell (FDC)-FcgammaRIIB levels are up-regulated 1-3 days after challenge of actively immunized mice with Ag. This kinetics suggested that memory cells are not driving this response, prompting the hypothesis that immune complex (IC)-FDC interactions lead to FDC activation. To test this, mice passively immunized with anti-OVA Ab were OVA challenged to produce IC. After 3 days, levels of IC, FcgammaRIIB, ICAM-1, and VCAM-1 on FDC were analyzed. FDC were also stimulated with IC in vitro, and mRNA for FcgammaRIIB, ICAM-1, and VCAM-1 was quantified by quantitative RT-PCR. IC labeling in passively immunized WT and FcgammaRIIB-/- mice revealed five to six FDC-reticula per LN midsagittal section. In WT mice, these IC-bearing FDC-reticula corresponded with FDC-reticula labeling for FcgammaRIIB, ICAM-1, and VCAM-1. Increases in these molecules on IC-stimulated FDC were confirmed by flow cytometry. In marked contrast, in FcgammaRIIB-/- mice, no increased VCAM-1 or ICAM-1 was seen on IC-bearing FDC-reticula or on purified FDC. Addition of IC in vitro resulted in dramatic increases in mRNA for FcgammaRIIB, ICAM-1 and VCAM-1 in WT FDC, but not in FDC from FcgammaRIIB-/- mice, 2.4G2-pretreated WT FDC, B cells, or macrophages. Thus, although FDC-FcgammaRIIB was not essential for IC trapping, engagement of FDC-FcgammaRIIB with IC initiated an FDC activation pathway.
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Affiliation(s)
- Mohey Eldin El Shikh
- Department of Microbiology and Immunology, Virginia Commonwealth University, Richmond, VA 23298-0678, USA
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23
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Abstract
During evolution, the development of secondary lymphoid organs has evolved as a strategy to promote adaptive immune responses at sites of antigen sequestration. Mesenteric lymph nodes (LNs) and Peyer's patches (PPs) are localized in proximity to mucosal surfaces, and their development is coordinated by a series of temporally and spatially regulated molecular events involving the collaboration between hematopoietic, mesenchymal, and, for PPs, epithelial cells. Transcriptional control of cellular differentiation, production of cytokines as well as adhesion molecules are mandatory for organogenesis, recruitment of mature leukocytes, and lymphoid tissue organization. Similar to fetal and neonatal organogenesis, lymphoid tissue neoformation can occur in adult individuals at sites of chronic stimulation via cytokines and TNF-family member molecules. These molecules represent new therapeutic targets to manipulate the microenvironment during autoimmune diseases.
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Affiliation(s)
- D Finke
- Center for Biomedicine, Developmental Immunology, Department of Clinical and Biological Sciences (DKBW), University of Basel, Mattenstrasse 28, 4058 Basel, Switzerland.
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24
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Muñoz-Fernández R, Blanco FJ, Frecha C, Martín F, Kimatrai M, Abadía-Molina AC, García-Pacheco JM, Olivares EG. Follicular dendritic cells are related to bone marrow stromal cell progenitors and to myofibroblasts. THE JOURNAL OF IMMUNOLOGY 2006; 177:280-9. [PMID: 16785523 DOI: 10.4049/jimmunol.177.1.280] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Follicular dendritic cells (FDC) are involved in the presentation of native Ags to B cells during the secondary immune response. Some authors consider FDC to be hemopoietic cells, whereas others believe them to be mesenchymal cells. The low proportion of FDC in the lymphoid follicle, together with technical difficulties in their isolation, make these cells difficult to study. We show that Fibroblast Medium can be used successfully to isolate and maintain FDC lines. In this culture medium, we obtained 18 FDC lines from human tonsils, which proliferated for as long as 18 wk and showed a stable Ag phenotype as detected by flow cytometry and RT-PCR. FDC lines were CD45-negative and expressed Ags associated to FDC (CD21, CD23, CD35, CD40, CD73, BAFF, ICAM-1, and VCAM-1) and Ags specific for FDC (DRC-1, CNA.42, and HJ2). These cell lines were also able to bind B cells and secrete CXCL13, functional activities characteristic of FDC. Nevertheless, the additional expression of STRO-1, together with CD10, CD13, CD29, CD34, CD63, CD73, CD90, ICAM-1, VCAM-1, HLA-DR, alkaline phosphatase, and alpha-smooth muscle actin (alpha-SM actin) indicated that FDC are closely related to bone marrow stromal cell progenitors. The expression of alpha-SM actin also relates FDC with myofibroblasts. Like myofibroblasts, FDC lines expressed stress fibers containing alpha-SM actin and were able to contract collagen gels under the effect of TGFbeta1 and platelet-derived growth factor. These findings suggest that FDC are a specialized form of myofibroblast and derive from bone marrow stromal cell progenitors.
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MESH Headings
- Actins/biosynthesis
- Actins/genetics
- Animals
- Antigens, CD/biosynthesis
- Antigens, CD/genetics
- B-Lymphocyte Subsets/immunology
- Bone Marrow Cells/cytology
- Bone Marrow Cells/immunology
- Bone Marrow Cells/metabolism
- Cell Adhesion/immunology
- Cell Line, Tumor
- Cell Lineage/immunology
- Cells, Cultured
- Child
- Child, Preschool
- Dendritic Cells, Follicular/cytology
- Dendritic Cells, Follicular/immunology
- Dendritic Cells, Follicular/metabolism
- Fibroblasts/cytology
- Fibroblasts/immunology
- Fibroblasts/metabolism
- Humans
- Immunophenotyping
- Lymphotoxin-alpha/pharmacology
- Lymphotoxin-beta
- Membrane Proteins/pharmacology
- Mice
- Muscle, Smooth/cytology
- Muscle, Smooth/immunology
- Muscle, Smooth/metabolism
- RNA, Messenger/biosynthesis
- Stem Cells/cytology
- Stem Cells/immunology
- Stem Cells/metabolism
- Stromal Cells/cytology
- Stromal Cells/immunology
- Stromal Cells/metabolism
- Tumor Necrosis Factor-alpha/pharmacology
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Affiliation(s)
- Raquel Muñoz-Fernández
- Unidad de Inmunología, Instituto de Biopatología y Medicina Regenerativa, Hospital Universitario San Cecilio, Universidad de Granada, Avenida de Madrid s/n, 18012 Granada, Spain
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25
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Tjin EPM, Bende RJ, Derksen PWB, van Huijstee AP, Kataoka H, Spaargaren M, Pals ST. Follicular dendritic cells catalyze hepatocyte growth factor (HGF) activation in the germinal center microenvironment by secreting the serine protease HGF activator. THE JOURNAL OF IMMUNOLOGY 2005; 175:2807-13. [PMID: 16116166 DOI: 10.4049/jimmunol.175.5.2807] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Ag-specific B cell differentiation, the process that gives rise to plasma cells and memory B cells, involves the formation of germinal centers (GC). Within the GC microenvironment, multiple steps of B cell proliferation, selection, and maturation take place, which are controlled by the BCR in concert with cytokines and contact-dependent signals from follicular dendritic cells (FDCs) and T cells. Signaling by the multifunctional cytokine hepatocyte growth factor (HGF) and its receptor MET has been shown to induce integrin-mediated adhesion of B cells to VCAM-1, which is expressed by FDCs. In the present study we have examined the expression of regulatory components of the HGF/MET pathway, including HGF activator (HGFA), within the secondary lymphoid organ microenvironment. We show that MET is expressed by both centroblasts and plasma cells, and that HGFA is expressed by plasma cells. Because we have shown that HGF is a potent growth and survival factor for malignant plasma cells, HGF may also serve as a survival factor for normal plasma cells. Furthermore, we demonstrate that FDCs are the major source for HGF and its activator within the GC microenvironment. Both HGF and HGFA are expressed by FDCs in the GC dark zone (CD21high/CD23low), but not in the light zone (CD21high/CD23high). These findings suggest that HGF and HGFA provided by dark zone FDCs help to regulate the proliferation, survival, and/or adhesion of MET-positive centroblasts.
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Affiliation(s)
- Esther P M Tjin
- Department of Pathology, Academic Medical Center, Amsterdam, The Netherlands
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26
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Wang Y, Carter RH. CD19 Regulates B Cell Maturation, Proliferation, and Positive Selection in the FDC Zone of Murine Splenic Germinal Centers. Immunity 2005; 22:749-61. [PMID: 15963789 DOI: 10.1016/j.immuni.2005.04.012] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2004] [Revised: 04/07/2005] [Accepted: 04/20/2005] [Indexed: 10/25/2022]
Abstract
Mice with mutations in CD19 Y482/Y513 form germinal centers (GC) but fail to produce high-affinity antibodies. In these mice, GC B cell differentiation, proliferation, and class switching occur but are defective. Altered CD19 signaling results in retention of early GC B cells and reduced proliferation in the follicular dendritic cell (FDC) zone of GC, and causes failure to select for high-affinity mutations. In normal mice, the earliest detectable aggregates of GC B cells are in contact with FDC and IgM+ cells are only found in the FDC zone, further evidence that the FDC zone is the site of initial GC B cell proliferation, differentiation, and class switching. Proliferation in the non-FDC zone and somatic mutation are not dependent on CD19, indicating separate signaling requirements for the two GC compartments, but these CD19-independent GC functions are not sufficient to generate high-affinity antibodies and B cell memory.
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Affiliation(s)
- Yue Wang
- Department of Medicine, The University of Alabama at Birmingham, Birmingham, Alabama 35294, USA
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27
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Sacedón R, Díez B, Nuñez V, Hernández-López C, Gutierrez-Frías C, Cejalvo T, Outram SV, Crompton T, Zapata AG, Vicente A, Varas A. Sonic hedgehog is produced by follicular dendritic cells and protects germinal center B cells from apoptosis. THE JOURNAL OF IMMUNOLOGY 2005; 174:1456-61. [PMID: 15661904 DOI: 10.4049/jimmunol.174.3.1456] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The Hedgehog (Hh) signaling pathway is involved in the development of many tissues during embryogenesis, but has also been described to function in adult self-renewing tissues. In the immune system, Sonic Hedgehog (Shh) regulates intrathymic T cell development and modulates the effector functions of peripheral CD4(+) T cells. In this study we investigate whether Shh signaling is involved in peripheral B cell differentiation in mice. Shh is produced by follicular dendritic cells, mainly in germinal centers (GCs), and GC B cells express both components of the Hh receptor, Patched and Smoothened. Blockade of the Hh signaling pathway reduces the survival, and consequently the proliferation and Ab secretion, of GC B cells. Furthermore, Shh rescues GC B cells from apoptosis induced by Fas ligation. Taken together, our data suggest that Shh is one of the survival signals provided by follicular dendritic cells to prevent apoptosis in GC B cells.
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Affiliation(s)
- Rosa Sacedón
- Department of Cell Biology, Faculty of Medicine, Complutense University, Madrid, Spain
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28
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Taylor RT, Lügering A, Newell KA, Williams IR. Intestinal cryptopatch formation in mice requires lymphotoxin alpha and the lymphotoxin beta receptor. THE JOURNAL OF IMMUNOLOGY 2005; 173:7183-9. [PMID: 15585839 DOI: 10.4049/jimmunol.173.12.7183] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Interactions between lymphotoxin (LT)alpha(1)beta(2) on inducer cells and the lymphotoxin beta receptor (LTbetaR) on stromal cells initiate development of lymph nodes and Peyer's patches. In this study, we assessed the contributions of LTalpha and LTbetaR to the development of cryptopatches (CP), aggregates of T cell precursors in the mouse small intestine. Mice genetically deficient in LTalpha or LTbetaR lacked CP. Bone marrow from LTalpha-deficient mice was unable to initiate development of CP or isolated lymphoid follicles (ILF) after transfer to CD132-null mice lacking CP and ILF. However, LTalpha-deficient bone marrow-derived cells contributed to CP formed in CD132-null mice receiving a mixture of wild-type and LTalpha-deficient bone marrow cells. Transfer of wild-type bone marrow into irradiated LTalpha-deficient mice resulted in reconstitution of both CP and ILF. However, the LT-dependent formation of CP was distinguished from the LT-dependent formation of ILF and Peyer's patches by not requiring the presence of an intact NF-kappaB-inducing kinase gene. CP but not ILF were present in the small intestine from NF-kappaB-inducing kinase-deficient alymphoplasia mice, indicating that the alternate NF-kappaB activation pathway required for other types of LTbetaR-dependent lymphoid organogenesis is dispensable for CP development. In addition, we identified VCAM-1(+) cells within both CP and ILF that are candidates for the stromal cells involved in receiving LT-dependent signals from the hemopoietic precursors recruited to CP. These findings demonstrate that interactions between cells expressing LTalpha(1)beta(2) and LTbetaR are a shared feature in the development of all small intestinal lymphoid aggregates.
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MESH Headings
- Animals
- Bone Marrow Transplantation/immunology
- Bone Marrow Transplantation/pathology
- Interleukin Receptor Common gamma Subunit
- Intestine, Small/immunology
- Intestine, Small/metabolism
- Intestine, Small/pathology
- Lymphocyte Subsets/cytology
- Lymphocyte Subsets/immunology
- Lymphocyte Subsets/transplantation
- Lymphoid Tissue/cytology
- Lymphoid Tissue/immunology
- Lymphoid Tissue/metabolism
- Lymphotoxin beta Receptor
- Lymphotoxin-alpha/deficiency
- Lymphotoxin-alpha/genetics
- Lymphotoxin-alpha/metabolism
- Lymphotoxin-alpha/physiology
- Lymphotoxin-beta
- Membrane Proteins/metabolism
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Mice, Mutant Strains
- Peyer's Patches/immunology
- Peyer's Patches/metabolism
- Peyer's Patches/pathology
- Receptors, Interleukin-7/deficiency
- Receptors, Interleukin-7/genetics
- Receptors, Tumor Necrosis Factor/deficiency
- Receptors, Tumor Necrosis Factor/genetics
- Receptors, Tumor Necrosis Factor/physiology
- Stem Cells/cytology
- Stem Cells/immunology
- Stem Cells/metabolism
- Stromal Cells/immunology
- Stromal Cells/metabolism
- Vascular Cell Adhesion Molecule-1/biosynthesis
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Affiliation(s)
- Rebekah T Taylor
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA
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29
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Whipple EC, Shanahan RS, Ditto AH, Taylor RP, Lindorfer MA. Analyses of the In Vivo Trafficking of Stoichiometric Doses of an Anti-Complement Receptor 1/2 Monoclonal Antibody Infused Intravenously in Mice. THE JOURNAL OF IMMUNOLOGY 2004; 173:2297-306. [PMID: 15294942 DOI: 10.4049/jimmunol.173.4.2297] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Complement plays a critical role in the immune response by opsonizing immune complexes (IC) and thymus-independent type 2 Ags with C3 breakdown product C3dg, a CR2-specific ligand. We used a C3dg-opsonized IC model, anti-CR1/2 mAb 7G6, to investigate how such substrates are processed. We used RIA, whole body imaging, flow cytometry, and fluorescence immunohistochemistry to examine the disposition of 0.1- to 2-microg quantities of mAb 7G6 infused i.v. into BALB/c mice. The mAb is rapidly taken up by the spleen and binds preferentially to marginal zone (MZ) B cells; within 24 h, the MZ B cells relocate and transfer mAb 7G6 to follicular dendritic cells (FDC). Transfer occurs coincident with loss of the extracellular portion of MZ B cell CR2, suggesting that the process may be mediated by proteolysis of CR2. Intravenous infusion of an FDC-specific mAb does not induce comparable splenic localization or cellular reorganization, emphasizing the importance of MZ B cells in intrasplenic trafficking of bound substrates. We propose the following mechanism: binding of C3dg-opsonized IC to noncognate MZ B cells promotes migration of these cells to the white pulp, followed by CR2 proteolysis, which allows transfer of the opsonized IC to FDC, thus facilitating presentation of intact Ags to cognate B cells.
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Affiliation(s)
- Emily C Whipple
- Department of Biochemistry and Molecular Genetics, University of Virginia, School of Medicine, Charlottesville, VA 22908, USA
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30
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Allen CDC, Ansel KM, Low C, Lesley R, Tamamura H, Fujii N, Cyster JG. Germinal center dark and light zone organization is mediated by CXCR4 and CXCR5. Nat Immunol 2004; 5:943-52. [PMID: 15300245 DOI: 10.1038/ni1100] [Citation(s) in RCA: 550] [Impact Index Per Article: 27.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2004] [Accepted: 06/25/2004] [Indexed: 12/30/2022]
Abstract
Germinal center (GC) dark and light zones segregate cells undergoing somatic hypermutation and antigen-driven selection, respectively, yet the factors guiding this organization are unknown. We report here that GC organization was absent from mice deficient in the chemokine receptor CXCR4. Centroblasts had high expression of CXCR4 and GC B cells migrated toward the CXCR4 ligand SDF-1 (CXCL12), which was more abundant in the dark zone than in the light zone. CXCR4-deficient cells were excluded from the dark zone in the context of a wild-type GC. These findings establish that GC organization depends on sorting of centroblasts by CXCR4 into the dark zone. In contrast, CXCR5 helped direct cells to the light zone and deficiency in CXCL13 was associated with aberrant light zone localization.
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MESH Headings
- Animals
- Antigen Presentation/immunology
- B-Lymphocytes/immunology
- Chemokine CXCL12
- Chemokine CXCL13
- Chemokines, CXC/immunology
- Chemokines, CXC/metabolism
- Chemotaxis, Leukocyte/immunology
- Flow Cytometry
- Germinal Center/cytology
- Germinal Center/immunology
- Immunohistochemistry
- Mice
- Mice, Transgenic
- Microdissection
- Radiation Chimera
- Rats
- Receptors, CXCR4/immunology
- Receptors, CXCR4/metabolism
- Receptors, CXCR5
- Receptors, Chemokine
- Receptors, Cytokine/immunology
- Receptors, Cytokine/metabolism
- Reverse Transcriptase Polymerase Chain Reaction
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Affiliation(s)
- Christopher D C Allen
- Howard Hughes Medical Institute and Department of Microbiology and Immunology, University of California San Francisco, San Francisco, California 94143-0414, USA
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31
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Kim HJ, Kammertoens T, Janke M, Schmetzer O, Qin Z, Berek C, Blankenstein T. Establishment of early lymphoid organ infrastructure in transplanted tumors mediated by local production of lymphotoxin alpha and in the combined absence of functional B and T cells. THE JOURNAL OF IMMUNOLOGY 2004; 172:4037-47. [PMID: 15034015 DOI: 10.4049/jimmunol.172.7.4037] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Lymphoid organogenesis is a highly coordinated process involving orchestrated expression of a number of genes. Although the essential role of lymphotoxin alpha (LTalpha) for the normal development of secondary lymphoid organs is well established, it is not clear to which extent it depends upon cooperation with T and B lymphocytes for lymphoid neo-organogenesis. To determine whether LTalpha is sufficient to mediate recruitment of basic elements needed for lymphoid organogenesis, we made use of a LTalpha-transfected cell line as an experimental tool and established tumors in nude and SCID mice. Our data showed that high endothelial venules formed and follicular dendritic cells accumulated and differentiated in response to LTalpha in the absence of lymphocytes. A CD4(+)CD3(-)CD11c(+) cell population that is found in the secondary lymphoid organ was also recruited into tumors expressing LTalpha. Furthermore, in nude mice, B cells migrated in response to LTalpha and formed intratumoral follicles. These B cell follicles were structurally well equipped with follicular dendritic cell networks and high endothelial venules; however, they were not functionally active; e.g., those B cells specific for a surrogate Ag expressed by the tumor were found in the spleen, but not in the tumor. We show that, even in the absence of functional T and B lymphocytes, local expression of LTalpha in transplanted tumors induced typical stromal characteristics of lymphoid tissue, emphasizing that LTalpha is a critically important cytokine for formation of lymphoid organ infrastructure.
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MESH Headings
- Animals
- B-Lymphocyte Subsets/immunology
- B-Lymphocyte Subsets/metabolism
- B-Lymphocyte Subsets/pathology
- CD11c Antigen/biosynthesis
- CD3 Complex/metabolism
- CD4-Positive T-Lymphocytes/immunology
- CD4-Positive T-Lymphocytes/metabolism
- CD4-Positive T-Lymphocytes/pathology
- Cell Line, Tumor
- Cell Movement/immunology
- Dendritic Cells, Follicular/immunology
- Dendritic Cells, Follicular/metabolism
- Dendritic Cells, Follicular/pathology
- Endothelium, Lymphatic/blood supply
- Endothelium, Lymphatic/immunology
- Endothelium, Lymphatic/pathology
- Humans
- Inflammation/immunology
- Inflammation/pathology
- Lymphoid Tissue/blood supply
- Lymphoid Tissue/immunology
- Lymphoid Tissue/pathology
- Lymphopenia/immunology
- Lymphopenia/pathology
- Lymphopoiesis/immunology
- Lymphotoxin-alpha/biosynthesis
- Lymphotoxin-alpha/genetics
- Lymphotoxin-alpha/metabolism
- Lymphotoxin-alpha/physiology
- Mice
- Mice, Inbred BALB C
- Mice, Nude
- Mice, SCID
- Neoplasm Transplantation/immunology
- Neoplasm Transplantation/pathology
- Plasmacytoma/immunology
- Plasmacytoma/metabolism
- Plasmacytoma/pathology
- T-Lymphocyte Subsets/immunology
- T-Lymphocyte Subsets/metabolism
- T-Lymphocyte Subsets/pathology
- Transfection
- Venules
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Affiliation(s)
- Hye-Jung Kim
- Institute of Immunology, Charité Campus Benjamin Franklin, Berlin, Germany
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32
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Cook-Mills JM, Johnson JD, Deem TL, Ochi A, Wang L, Zheng Y. Calcium mobilization and Rac1 activation are required for VCAM-1 (vascular cell adhesion molecule-1) stimulation of NADPH oxidase activity. Biochem J 2004; 378:539-47. [PMID: 14594451 PMCID: PMC1223954 DOI: 10.1042/bj20030794] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2003] [Revised: 10/23/2003] [Accepted: 10/31/2003] [Indexed: 01/12/2023]
Abstract
VCAM-1 (vascular cell adhesion molecule-1) plays an important role in the regulation of inflammation in atherosclerosis, asthma, inflammatory bowel disease and transplantation. VCAM-1 activates endothelial cell NADPH oxidase, and this oxidase activity is required for VCAM-1-dependent lymphocyte migration. We reported previously that a mouse microvascular endothelial cell line promotes lymphocyte migration that is dependent on VCAM-1, but not on other known adhesion molecules. Here we have investigated the signalling mechanisms underlying VCAM-1 function. Lymphocyte binding to VCAM-1 on the endothelial cell surface activated an endothelial cell calcium flux that could be inhibited with anti-alpha4-integrin and mimicked by anti-VCAM-1-coated beads. VCAM-1 stimulation of calcium responses could be blocked by an inhibitor of intracellular calcium mobilization, a calcium channel inhibitor or a calcium chelator, resulting in the inhibition of NADPH oxidase activity. Addition of ionomycin overcame the calcium channel blocker suppression of VCAM-1-stimulated NADPH oxidase activity, but could not reverse the inhibitory effect imposed by intracellular calcium blockage, indicating that both intracellular and extracellular calcium mobilization are required for VCAM-1-mediated activation of NADPH oxidase. Furthermore, VCAM-1 specifically activated the Rho-family GTPase Rac1, and VCAM-1 activation of NADPH oxidase was blocked by a dominant negative Rac1. Thus VCAM-1 stimulates the mobilization of intracellular and extracellular calcium and Rac1 activity that are required for the activation of NADPH oxidase.
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Affiliation(s)
- Joan M Cook-Mills
- Department of Pathology, University of Cincinnati, Cincinnati, OH 45267-0529, USA.
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33
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Gommerman JL, Browning JL. Lymphotoxin/light, lymphoid microenvironments and autoimmune disease. Nat Rev Immunol 2003; 3:642-55. [PMID: 12974479 DOI: 10.1038/nri1151] [Citation(s) in RCA: 224] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Much of the efficiency of the immune system is attributed to the high degree of spatial and temporal organization in the secondary lymphoid organs. Signalling through the lymphotoxin (LT) pathway is a crucial element in the maintenance of this organized microenvironment. The effect of altering lymphoid microenvironments on immune responses remains relatively unexplored. Inhibitors of the LT and LIGHT pathways have been shown to reduce disease in a wide range of autoimmune models. This approach has provided a tool to probe the effect of manipulation of the microenvironment on both normal and pathological immune responses.
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Affiliation(s)
- Jennifer L Gommerman
- Biogen, Department of Exploratory Sciences, 12 Cambridge Center, Cambridge, Massachusetts 02142, USA
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