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Wheeler AE, Stoeger V, Owens RM. Lab-on-chip technologies for exploring the gut-immune axis in metabolic disease. LAB ON A CHIP 2024; 24:1266-1292. [PMID: 38226866 DOI: 10.1039/d3lc00877k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/17/2024]
Abstract
The continued rise in metabolic diseases such as obesity and type 2 diabetes mellitus poses a global health burden, necessitating further research into factors implicated in the onset and progression of these diseases. Recently, the gut-immune axis, with diet as a main regulator, has been identified as a possible role player in their development. Translation of conventional 2D in vitro and animal models is however limited, while human studies are expensive and preclude individual mechanisms from being investigated. Lab-on-chip technology therefore offers an attractive new avenue to study gut-immune interactions. This review provides an overview of the influence of diet on gut-immune interactions in metabolic diseases and a critical analysis of the current state of lab-on-chip technology to study this axis. While there has been progress in the development of "immuno-competent" intestinal lab-on-chip models, with studies showing the ability of the technology to provide mechanical cues, support longer-term co-culture of microbiota and maintain in vivo-like oxygen gradients, platforms which combine all three and include intestinal and immune cells are still lacking. Further, immune cell types and inclusion of microenvironment conditions which enable in vivo-like immune cell dynamics as well as host-microbiome interactions are limited. Future model development should focus on combining these conditions to create an environment capable of hosting more complex microbiota and immune cells to allow further study into the effects of diet and related metabolites on the gut-immune ecosystem and their role in the prevention and development of metabolic diseases in humans.
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Affiliation(s)
- Alexandra E Wheeler
- Department of Chemical Engineering and Biotechnology, University of Cambridge, UK.
| | - Verena Stoeger
- Department of Chemical Engineering and Biotechnology, University of Cambridge, UK.
| | - Róisín M Owens
- Department of Chemical Engineering and Biotechnology, University of Cambridge, UK.
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2
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Nowosad C. Who goes there? Science 2024; 383:714. [PMID: 38359136 DOI: 10.1126/science.adn9414] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2024]
Abstract
How B cells assess risk in the intestine.
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Affiliation(s)
- Carla Nowosad
- Department of Pathology, NYU Langone, Grossman School of Medicine, New York University, New York, NY, USA
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3
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Raso F, Liu S, Simpson MJ, Barton GM, Mayer CT, Acharya M, Muppidi JR, Marshak-Rothstein A, Reboldi A. Antigen receptor signaling and cell death resistance controls intestinal humoral response zonation. Immunity 2023; 56:2373-2387.e8. [PMID: 37714151 PMCID: PMC10591993 DOI: 10.1016/j.immuni.2023.08.018] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2023] [Revised: 05/24/2023] [Accepted: 08/21/2023] [Indexed: 09/17/2023]
Abstract
Immunoglobulin A (IgA) maintains commensal communities in the intestine while preventing dysbiosis. IgA generated against intestinal microbes assures the simultaneous binding to multiple, diverse commensal-derived antigens. However, the exact mechanisms by which B cells mount broadly reactive IgA to the gut microbiome remains elusive. Here, we have shown that IgA B cell receptor (BCR) is required for B cell fitness during the germinal center (GC) reaction in Peyer's patches (PPs) and for generation of gut-homing plasma cells (PCs). We demonstrate that IgA BCR drove heightened intracellular signaling in mouse and human B cells, and as a consequence, IgA+ B cells received stronger positive selection cues. Mechanistically, IgA BCR signaling offset Fas-mediated death, possibly rescuing low-affinity B cells to promote a broad humoral response to commensals. Our findings reveal an additional mechanism linking BCR signaling, B cell fate, and antibody production location, which have implications for how intestinal antigen recognition shapes humoral immunity.
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Affiliation(s)
- Fiona Raso
- Department of Pathology, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Shuozhi Liu
- Seattle Children's Research Institute, Seattle, WA, USA
| | - Mikala J Simpson
- Experimental Immunology Branch, Center for Cancer Research, NCI, NIH, Bethesda, MD, USA
| | - Gregory M Barton
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA
| | - Christian T Mayer
- Experimental Immunology Branch, Center for Cancer Research, NCI, NIH, Bethesda, MD, USA
| | - Mridu Acharya
- Seattle Children's Research Institute, Seattle, WA, USA; Department of Pediatrics, University of Washington, Seattle, WA, USA
| | - Jagan R Muppidi
- Lymphoid Malignancies Branch, Center for Cancer Research, NCI, NIH, Bethesda, MD, USA
| | - Ann Marshak-Rothstein
- Department of Medicine, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Andrea Reboldi
- Department of Pathology, University of Massachusetts Chan Medical School, Worcester, MA, USA.
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4
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Pabst O, Nowosad CR. B cells and the intestinal microbiome in time, space and place. Semin Immunol 2023; 69:101806. [PMID: 37473559 DOI: 10.1016/j.smim.2023.101806] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Accepted: 07/08/2023] [Indexed: 07/22/2023]
Abstract
The gut immune system is shaped by the continuous interaction with the microbiota. Here we dissect temporal, spatial and contextual layers of gut B cell responses. The microbiota impacts on the selection of the developing pool of pre-immune B cells that serves as substrate for B cell activation, expansion and differentiation. However, various aspects of the gut B cell response display unique features. In particular, occurrence of somatically mutated B cells, chronic gut germinal centers in T cell-deficient settings and polyreactive binding of gut IgA to the microbiota questioned the nature and microbiota-specificity of gut germinal centers. We propose a model to reconcile these observations incorporating recent work demonstrating microbiota-specificity of gut germinal centers. We speculate that adjuvant effects of the microbiota might modify permissiveness for B cell to enter and exit gut germinal centers. We propose that separating aspects of time, space and place facilitate the occasionally puzzling discussion of gut B cell responses to the microbiota.
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Affiliation(s)
- Oliver Pabst
- Institute of Molecular Medicine, RWTH Aachen University, Aachen, Germany.
| | - Carla R Nowosad
- Department of Pathology, NYU Grossman School of Medicine, New York University, New York, USA; Translational Immunology Center, NYU Grossman School of Medicine, New York University, New York, USA.
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5
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Rivera CE, Zhou Y, Chupp DP, Yan H, Fisher AD, Simon R, Zan H, Xu Z, Casali P. Intrinsic B cell TLR-BCR linked coengagement induces class-switched, hypermutated, neutralizing antibody responses in absence of T cells. SCIENCE ADVANCES 2023; 9:eade8928. [PMID: 37115935 PMCID: PMC10146914 DOI: 10.1126/sciadv.ade8928] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Accepted: 03/23/2023] [Indexed: 05/03/2023]
Abstract
Maturation of antibody responses entails somatic hypermutation (SHM), class-switch DNA recombination (CSR), plasma cell differentiation, and generation of memory B cells, and it is thought to require T cell help. We showed that B cell Toll-like receptor 4 (TLR4)-B cell receptor (BCR) (receptor for antigen) coengagement by 4-hydroxy-3-nitrophenyl acetyl (NP)-lipopolysaccharide (LPS) (Escherichia coli lipid A polysaccharide O-antigen) or TLR5-BCR coengagement by Salmonella flagellin induces mature antibody responses to NP and flagellin in Tcrβ-/-Tcrδ-/- and NSG/B mice. TLR-BCR coengagement required linkage of TLR and BCR ligands, "linked coengagement." This induced B cell CSR/SHM, germinal center-like differentiation, clonal expansion, intraconal diversification, plasma cell differentiation, and an anamnestic antibody response. In Tcrβ-/-Tcrδ-/- mice, linked coengagement of TLR4-BCR by LPS or TLR5-BCR by flagellin induced protective antibodies against E. coli or Salmonella Typhimurium. Our findings unveiled a critical role of B cell TLRs in inducing neutralizing antibody responses, including those to microbial pathogens, without T cell help.
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Affiliation(s)
- Carlos E. Rivera
- Department of Microbiology, Immunology & Molecular Genetics, University of Texas Long School of Medicine, UT Health Science Center, San Antonio, TX 78229, USA
| | - Yulai Zhou
- Department of Microbiology, Immunology & Molecular Genetics, University of Texas Long School of Medicine, UT Health Science Center, San Antonio, TX 78229, USA
| | - Daniel P. Chupp
- Department of Microbiology, Immunology & Molecular Genetics, University of Texas Long School of Medicine, UT Health Science Center, San Antonio, TX 78229, USA
| | - Hui Yan
- Department of Microbiology, Immunology & Molecular Genetics, University of Texas Long School of Medicine, UT Health Science Center, San Antonio, TX 78229, USA
| | - Amanda D. Fisher
- Department of Microbiology, Immunology & Molecular Genetics, University of Texas Long School of Medicine, UT Health Science Center, San Antonio, TX 78229, USA
| | - Raphael Simon
- Center for Vaccine Development, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Hong Zan
- Department of Microbiology, Immunology & Molecular Genetics, University of Texas Long School of Medicine, UT Health Science Center, San Antonio, TX 78229, USA
| | - Zhenming Xu
- Department of Microbiology, Immunology & Molecular Genetics, University of Texas Long School of Medicine, UT Health Science Center, San Antonio, TX 78229, USA
| | - Paolo Casali
- Department of Microbiology, Immunology & Molecular Genetics, University of Texas Long School of Medicine, UT Health Science Center, San Antonio, TX 78229, USA
- Department of Medicine, University of Texas Long School of Medicine, UT Health Science Center, San Antonio, TX 78229, USA
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6
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Spencer J, Bemark M. Human intestinal B cells in inflammatory diseases. Nat Rev Gastroenterol Hepatol 2023; 20:254-265. [PMID: 36849542 DOI: 10.1038/s41575-023-00755-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 02/07/2023] [Indexed: 03/01/2023]
Abstract
The intestinal lumen contains an abundance of bacteria, viruses and fungi alongside ingested material that shape the chronically active intestinal immune system from early life to maintain the integrity of the gut epithelial barrier. In health, the response is intricately balanced to provide active protection against pathogen invasion whilst tolerating food and avoiding inflammation. B cells are central to achieving this protection. Their activation and maturation generates the body's largest plasma cell population that secretes IgA, and the niches they provide support systemic immune cell specialization. For example, the gut supports the development and maturation of a splenic B cell subset - the marginal zone B cells. In addition, cells such as the T follicular helper cells, which are enriched in many autoinflammatory diseases, are intrinsically associated with the germinal centre microenvironment that is more abundant in the gut than in any other tissue in health. In this Review, we discuss intestinal B cells and their role when a loss of homeostasis results in intestinal and systemic inflammatory diseases.
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Affiliation(s)
- Jo Spencer
- School of Immunology and Microbial Sciences, King's College London, Guy's Campus, London, UK.
| | - Mats Bemark
- Department of Microbiology and Immunology, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
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7
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Ng KW, Hobbs A, Wichmann C, Victora GD, Donaldson GP. B cell responses to the gut microbiota. Adv Immunol 2022; 155:95-131. [PMID: 36357013 DOI: 10.1016/bs.ai.2022.08.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Most antibody produced by humans originates from mucosal B cell responses. The rules, mechanisms, and outcomes of this process are distinct from B cell responses to infection. Within the context of the intestine, we discuss the induction of follicular B cell responses by microbiota, the development and maintenance of mucosal antibody-secreting cells, and the unusual impacts of mucosal antibody on commensal bacteria. Much remains to be learned about the interplay between B cells and the microbiota, but past and present work hints at a complex, nuanced relationship that may be critical to the way the mammalian gut fosters a beneficial microbial ecosystem.
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Affiliation(s)
- Kevin W Ng
- Laboratory of Lymphocyte Dynamics, The Rockefeller University, New York, NY, United States
| | - Alvaro Hobbs
- Laboratory of Lymphocyte Dynamics, The Rockefeller University, New York, NY, United States
| | - Christopher Wichmann
- Laboratory of Lymphocyte Dynamics, The Rockefeller University, New York, NY, United States; Laboratory of Mucosal Immunology, The Rockefeller University, New York, NY, United States; Immune Regulation Group, Department of Pediatrics, University Medical Center Rostock, Rostock, Germany
| | - Gabriel D Victora
- Laboratory of Lymphocyte Dynamics, The Rockefeller University, New York, NY, United States.
| | - Gregory P Donaldson
- Laboratory of Mucosal Immunology, The Rockefeller University, New York, NY, United States.
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8
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Jones ST, Guo K, Cooper EH, Dillon SM, Wood C, Nguyen DH, Shen G, Barrett BS, Frank DN, Kroehl M, Janoff EN, Kechris K, Wilson CC, Santiago ML. Altered Immunoglobulin Repertoire and Decreased IgA Somatic Hypermutation in the Gut during Chronic HIV-1 Infection. J Virol 2022; 96:e0097622. [PMID: 35938870 PMCID: PMC9472609 DOI: 10.1128/jvi.00976-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Accepted: 07/21/2022] [Indexed: 11/27/2022] Open
Abstract
Humoral immune perturbations contribute to pathogenic outcomes in persons with HIV-1 infection (PWH). Gut barrier dysfunction in PWH is associated with microbial translocation and alterations in microbial communities (dysbiosis), and IgA, the most abundant immunoglobulin (Ig) isotype in the gut, is involved in gut homeostasis by interacting with the microbiome. We determined the impact of HIV-1 infection on the antibody repertoire in the gastrointestinal tract by comparing Ig gene utilization and somatic hypermutation (SHM) in colon biopsies from PWH (n = 19) versus age and sex-matched controls (n = 13). We correlated these Ig parameters with clinical, immunological, microbiome and virological data. Gene signatures of enhanced B cell activation were accompanied by skewed frequencies of multiple Ig Variable genes in PWH. PWH showed decreased frequencies of SHM in IgA and possibly IgG, with a substantial loss of highly mutated IgA sequences. The decline in IgA SHM in PWH correlated with gut CD4+ T cell loss and inversely correlated with mucosal inflammation and microbial translocation. Diminished gut IgA SHM in PWH was driven by transversion mutations at A or T deoxynucleotides, suggesting a defect not at the AID/APOBEC3 deamination step but at later stages of IgA SHM. These results expand our understanding of humoral immune perturbations in PWH that could have important implications in understanding mucosal immune defects in individuals with chronic HIV-1 infection. IMPORTANCE The gut is a major site of early HIV-1 replication and pathogenesis. Extensive CD4+ T cell depletion in this compartment results in a compromised epithelial barrier that facilitates the translocation of microbes into the underlying lamina propria and systemic circulation, resulting in chronic immune activation. To date, the consequences of microbial translocation on the mucosal humoral immune response (or vice versa) remains poorly integrated into the panoply of mucosal immune defects in PWH. We utilized next-generation sequencing approaches to profile the Ab repertoire and ascertain frequencies of somatic hypermutation in colon biopsies from antiretroviral therapy-naive PWH versus controls. Our findings identify perturbations in the Ab repertoire of PWH that could contribute to development or maintenance of dysbiosis. Moreover, IgA mutations significantly decreased in PWH and this was associated with adverse clinical outcomes. These data may provide insight into the mechanisms underlying impaired Ab-dependent gut homeostasis during chronic HIV-1 infection.
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Affiliation(s)
- Sean T. Jones
- Division of Infectious Diseases, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
- Department of Immunology and Microbiology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Kejun Guo
- Division of Infectious Diseases, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
- RNA Bioscience Initiative, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Emily H. Cooper
- Center for Innovative Design and Analysis, Department of Biostatistics and Informatics, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Stephanie M. Dillon
- Division of Infectious Diseases, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Cheyret Wood
- Center for Innovative Design and Analysis, Department of Biostatistics and Informatics, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - David H. Nguyen
- Division of Infectious Diseases, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Guannan Shen
- Center for Innovative Design and Analysis, Department of Biostatistics and Informatics, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Bradley S. Barrett
- Division of Infectious Diseases, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Daniel N. Frank
- Division of Infectious Diseases, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Miranda Kroehl
- Center for Innovative Design and Analysis, Department of Biostatistics and Informatics, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Edward N. Janoff
- Division of Infectious Diseases, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
- Department of Immunology and Microbiology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
- Rocky Mountain Regional Veterans Affairs Medical Center, Aurora, Colorado, USA
| | - Katerina Kechris
- Center for Innovative Design and Analysis, Department of Biostatistics and Informatics, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Cara C. Wilson
- Division of Infectious Diseases, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
- Department of Immunology and Microbiology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
- RNA Bioscience Initiative, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Mario L. Santiago
- Division of Infectious Diseases, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
- Department of Immunology and Microbiology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
- RNA Bioscience Initiative, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
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9
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León ED, Francino MP. Roles of Secretory Immunoglobulin A in Host-Microbiota Interactions in the Gut Ecosystem. Front Microbiol 2022; 13:880484. [PMID: 35722300 PMCID: PMC9203039 DOI: 10.3389/fmicb.2022.880484] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Accepted: 05/09/2022] [Indexed: 12/12/2022] Open
Abstract
In the gastrointestinal tract (GIT), the immune system interacts with a variety of microorganisms, including pathogens as well as beneficial symbionts that perform important physiological functions for the host and are crucial to sustain intestinal homeostasis. In normal conditions, secretory immunoglobulin A (SIgA) is the principal antibody produced by B cells in the GIT mucosa. Polyreactivity provides certain SIgA molecules with the ability of binding different antigens in the bacterial surface, such as O-antigens and teichoic acids, while cross-species reactivity allows them to recognize and interact with different types of bacteria. These functions may be crucial in allowing SIgA to modulate the complex gut microbiota in an efficient manner. Several studies suggest that SIgA can help with the retention and proliferation of helpful members of the gut microbiota. Gut microbiota alterations in people with IgA deficiency include the lack of some species that are known to be normally coated by SIgA. Here, we discuss the different ways in which SIgA behaves in relation to pathogens and beneficial bacteria of the gut microbiota and how the immune system might protect and facilitate the establishment and maintenance of certain gut symbionts.
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Affiliation(s)
- E Daniel León
- Department of Genomics and Health, Fundación Para el Fomento de la Investigación Sanitaria y Biomédica de la Comunitat Valenciana (FISABIO), Valencia, Spain
| | - M Pilar Francino
- Department of Genomics and Health, Fundación Para el Fomento de la Investigación Sanitaria y Biomédica de la Comunitat Valenciana (FISABIO), Valencia, Spain.,CIBER en Epidemiología y Salud Pública, Madrid, Spain
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10
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Seikrit C, Pabst O. The immune landscape of IgA induction in the gut. Semin Immunopathol 2021; 43:627-637. [PMID: 34379174 PMCID: PMC8551147 DOI: 10.1007/s00281-021-00879-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Accepted: 06/09/2021] [Indexed: 12/14/2022]
Abstract
Antibodies are key elements of protective immunity. In the mucosal immune system in particular, secretory immunoglobulin A (SIgA), the most abundantly produced antibody isotype, protects against infections, shields the mucosal surface from toxins and environmental factors, and regulates immune homeostasis and a peaceful coexistence with our microbiota. However, the dark side of IgA biology promotes the formation of immune complexes and provokes pathologies, e.g., IgA nephropathy (IgAN). The precise mechanisms of how IgA responses become deregulated and pathogenic in IgAN remain unresolved. Yet, as the field of microbiota research moved into the limelight, our basic understanding of IgA biology has been taking a leap forward. Here, we discuss the structure of IgA, the anatomical and cellular foundation of mucosal antibody responses, and current concepts of how we envision the interaction of SIgA and the microbiota. We center on key concepts in the field while taking account of both historic findings and exciting new observations to provide a comprehensive groundwork for the understanding of IgA biology from the perspective of a mucosal immunologist.
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Affiliation(s)
- Claudia Seikrit
- Division of Nephrology and Clinical Immunology, RWTH Aachen University, Aachen, Germany
| | - Oliver Pabst
- Institute of Molecular Medicine, RWTH Aachen University, Pauwelsstr. 30, 52074, Aachen, Germany.
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11
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Bemark M, Angeletti D. Know your enemy or find your friend?-Induction of IgA at mucosal surfaces. Immunol Rev 2021; 303:83-102. [PMID: 34331314 PMCID: PMC7612940 DOI: 10.1111/imr.13014] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Accepted: 06/28/2021] [Indexed: 12/15/2022]
Abstract
Most antibodies produced in the body are of the IgA class. The dominant cell population producing them are plasma cells within the lamina propria of the gastrointestinal tract, but many IgA-producing cells are also found in the airways, within mammary tissues, the urogenital tract and inside the bone marrow. Most IgA antibodies are transported into the lumen by epithelial cells as part of the mucosal secretions, but they are also present in serum and other body fluids. A large part of the commensal microbiota in the gut is covered with IgA antibodies, and it has been demonstrated that this plays a role in maintaining a healthy balance between the host and the bacteria. However, IgA antibodies also play important roles in neutralizing pathogens in the gastrointestinal tract and the upper airways. The distinction between the two roles of IgA - protective and balance-maintaining - not only has implications on function but also on how the production is regulated. Here, we discuss these issues with a special focus on gut and airways.
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Affiliation(s)
- Mats Bemark
- Department of Microbiology and Immunology, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.,Department of Clinical Immunology and Transfusion Medicine, Region Västra Götaland, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Davide Angeletti
- Department of Microbiology and Immunology, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
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12
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Human gut-associated lymphoid tissues (GALT); diversity, structure, and function. Mucosal Immunol 2021; 14:793-802. [PMID: 33753873 DOI: 10.1038/s41385-021-00389-4] [Citation(s) in RCA: 147] [Impact Index Per Article: 49.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 02/05/2021] [Accepted: 02/06/2021] [Indexed: 02/07/2023]
Abstract
Gut-associated lymphoid tissues (GALT) are the key antigen sampling and adaptive immune inductive sites within the intestinal wall. Human GALT includes the multi-follicular Peyer's patches of the ileum, the vermiform appendix, and the numerous isolated lymphoid follicles (ILF) which are distributed along the length of the intestine. Our current understanding of GALT diversity and function derives primarily from studies in mice, and the relevance of many of these findings to human GALT remains unclear. Here we review our current understanding of human GALT diversity, structure, and composition as well as their potential for regulating intestinal immune responses during homeostasis and inflammatory bowel disease (IBD). Finally, we outline some key remaining questions regarding human GALT, the answers to which will advance our understanding of intestinal immune responses and provide potential opportunities to improve the treatment of intestinal diseases.
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13
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Kabbert J, Benckert J, Rollenske T, Hitch TCA, Clavel T, Cerovic V, Wardemann H, Pabst O. High microbiota reactivity of adult human intestinal IgA requires somatic mutations. J Exp Med 2021; 217:151927. [PMID: 32640466 PMCID: PMC7526496 DOI: 10.1084/jem.20200275] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Revised: 05/25/2020] [Accepted: 06/22/2020] [Indexed: 12/11/2022] Open
Abstract
The gut is home to the body’s largest population of plasma cells. In healthy individuals, IgA is the dominating isotype, whereas patients with inflammatory bowel disease also produce high concentrations of IgG. In the gut lumen, secretory IgA binds pathogens and toxins but also the microbiota. However, the antigen specificity of IgA and IgG for the microbiota and underlying mechanisms of antibody binding to bacteria are largely unknown. Here we show that microbiota binding is a defining property of human intestinal antibodies in both healthy and inflamed gut. Some bacterial taxa were commonly targeted by different monoclonal antibodies, whereas others selectively bound single antibodies. Interestingly, individual human monoclonal antibodies from both healthy and inflamed intestines bound phylogenetically unrelated bacterial species. This microbiota cross-species reactivity did not correlate with antibody polyreactivity but was crucially dependent on the accumulation of somatic mutations. Therefore, our data suggest that a system of affinity-matured, microbiota cross-species–reactive IgA is a common aspect of SIgA–microbiota interactions in the gut.
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Affiliation(s)
- Johanna Kabbert
- Institute of Molecular Medicine, Rheinisch-Westfälische Technische Hochschule Aachen University, Aachen, Germany
| | - Julia Benckert
- Max Planck Research Group Molecular Immunology, Max Planck Institute for Infection Biology, Berlin, Germany.,Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany
| | - Tim Rollenske
- B Cell Immunology, German Cancer Research Centre, Heidelberg, Germany
| | - Thomas C A Hitch
- Functional Microbiome Research Group, Institute of Medical Microbiology, Rheinisch-Westfälische Technische Hochschule Aachen University, Aachen, Germany
| | - Thomas Clavel
- Functional Microbiome Research Group, Institute of Medical Microbiology, Rheinisch-Westfälische Technische Hochschule Aachen University, Aachen, Germany
| | - Vuk Cerovic
- Institute of Molecular Medicine, Rheinisch-Westfälische Technische Hochschule Aachen University, Aachen, Germany
| | - Hedda Wardemann
- B Cell Immunology, German Cancer Research Centre, Heidelberg, Germany
| | - Oliver Pabst
- Institute of Molecular Medicine, Rheinisch-Westfälische Technische Hochschule Aachen University, Aachen, Germany
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14
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Yang Y, Palm NW. Immunoglobulin A and the microbiome. Curr Opin Microbiol 2020; 56:89-96. [PMID: 32889295 DOI: 10.1016/j.mib.2020.08.003] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Revised: 08/06/2020] [Accepted: 08/07/2020] [Indexed: 01/06/2023]
Abstract
The trillions of microbes that constitutively colonize the intestine (the gut microbiota) impact diverse aspects of human physiology in health and disease. Immunoglobulin A (IgA) is the most abundant antibody isotype produced at mucosal surfaces, and nearly two grams of IgA is secreted into the intestine every day. Secretory IgA (SIgA) provides critical protection against pathogens and toxins, but can also directly bind to and 'coat' commensal bacteria in the gut. Commensal targeting by SIgA shapes gut microbiota composition, modulates bacterial behaviors, and enforces host-microbiota homeostasis in both mice and humans.
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Affiliation(s)
- Yi Yang
- Department of Immunobiology, Yale University School of Medicine, New Haven, CT, USA
| | - Noah W Palm
- Department of Immunobiology, Yale University School of Medicine, New Haven, CT, USA.
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15
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Colafrancesco S, Priori R, Smith CG, Minniti A, Iannizzotto V, Pipi E, Lucchesi D, Pontarini E, Nayar S, Campos J, Arienzo F, Fusconi M, Cerbelli B, Giordano C, Valesini G, Bombardieri M, Fisher BA, Barone F. CXCL13 as biomarker for histological involvement in Sjögren's syndrome. Rheumatology (Oxford) 2020; 59:165-170. [PMID: 31274159 DOI: 10.1093/rheumatology/kez255] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Revised: 05/26/2019] [Indexed: 02/06/2023] Open
Abstract
OBJECTIVES SS is an autoimmune condition characterized by systemic B-cell activation, autoantibody production and ectopic germinal centres' formation within the salivary gland (SG). The extent of SG infiltrate has been proposed as a biomarker of disease severity. Plasma levels of CXCL13 correlate with germinal centres' activity in animal models and disease severity in SS, suggesting its potential use as a surrogate serum marker to monitor local B-cell activation. The aim of this study was to evaluate the potential role of CXCL13 as a biomarker of SG pathology in two independent SS cohorts. METHODS 109 patients with SS were recruited at Sapienza University of Rome (Italy) (n = 60), or at Queen Elizabeth Hospital in Birmingham and Barts Health NHS Trust in London (n = 49). Both sera and matched minor SG biopsy were available. Sicca (n = 57) and healthy subjects' (n = 19) sera were used as control. RESULTS CXCL13 serum level was higher in SS patients compared with controls. Correlations between its serum levels and a series of histomorphological parameters, including size of the aggregates and the presence germinal centres', were observed. CONCLUSION Our data foster the use of CXCL13 to monitor the extent of local pathology in SS and its validation in longitudinal clinical studies.
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Affiliation(s)
- Serena Colafrancesco
- Dipartimento di Medicina Interna e Specialità Mediche, Rheumatology Unit, Sapienza University, Rome, Italy
| | - Roberta Priori
- Dipartimento di Medicina Interna e Specialità Mediche, Rheumatology Unit, Sapienza University, Rome, Italy
| | - Charlotte G Smith
- Rheumatology Research Group, Institute of Inflammation and Ageing, University of Birmingham, Birmingham, UK
| | - Antonina Minniti
- Dipartimento di Medicina Interna e Specialità Mediche, Rheumatology Unit, Sapienza University, Rome, Italy
| | - Valentina Iannizzotto
- Rheumatology Research Group, Institute of Inflammation and Ageing, University of Birmingham, Birmingham, UK
| | - Elena Pipi
- Rheumatology Research Group, Institute of Inflammation and Ageing, University of Birmingham, Birmingham, UK
| | - Davide Lucchesi
- Centre for Experimental Medicine and Rheumatology, William Harvey Research Institute, Bart's and the London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - Elena Pontarini
- Centre for Experimental Medicine and Rheumatology, William Harvey Research Institute, Bart's and the London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - Saba Nayar
- Rheumatology Research Group, Institute of Inflammation and Ageing, University of Birmingham, Birmingham, UK
| | - Joana Campos
- Rheumatology Research Group, Institute of Inflammation and Ageing, University of Birmingham, Birmingham, UK
| | - Francesca Arienzo
- Dipartimento di Medicina Interna e Specialità Mediche, Rheumatology Unit, Sapienza University, Rome, Italy
| | - Massimo Fusconi
- Department of Sense Organs, Sapienza University of Rome, Rome, Italy
| | - Bruna Cerbelli
- Department of Radiological, Oncological and Pathological Sciences, Sapienza University of Rome, Rome, Italy
| | - Carla Giordano
- Department of Radiological, Oncological and Pathological Sciences, Sapienza University of Rome, Rome, Italy
| | - Guido Valesini
- Dipartimento di Medicina Interna e Specialità Mediche, Rheumatology Unit, Sapienza University, Rome, Italy
| | - Michele Bombardieri
- Centre for Experimental Medicine and Rheumatology, William Harvey Research Institute, Bart's and the London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - Benjamin A Fisher
- Rheumatology Research Group, Institute of Inflammation and Ageing, University of Birmingham, Birmingham, UK.,National Institute for Health Research (NIHR) Birmingham Biomedical Research Centre, University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK
| | - Francesca Barone
- Rheumatology Research Group, Institute of Inflammation and Ageing, University of Birmingham, Birmingham, UK.,National Institute for Health Research (NIHR) Birmingham Biomedical Research Centre, University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK
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16
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Pabst O, Slack E. IgA and the intestinal microbiota: the importance of being specific. Mucosal Immunol 2020; 13:12-21. [PMID: 31740744 PMCID: PMC6914667 DOI: 10.1038/s41385-019-0227-4] [Citation(s) in RCA: 236] [Impact Index Per Article: 59.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Revised: 09/27/2019] [Accepted: 09/28/2019] [Indexed: 02/04/2023]
Abstract
Secretory IgA has long been a divisive molecule. Some immunologists point to the mild phenotype of IgA deficiency to justify ignoring it, while some consider its abundance and evolutionary history as grounds for its importance. Further, there is extensive and growing disagreement over the relative importance of affinity-matured, T cell-dependent IgA vs. "natural" and T cell-independent IgA in both microbiota and infection control. As with all good arguments, there is good data supporting different opinions. Here we revisit longstanding questions in IgA biology. We start the discussion from the question of intestinal IgA antigen specificity and critical definitions regarding IgA induction, specificity, and function. These definitions must then be tessellated with the cellular and molecular pathways shaping IgA responses, and the mechanisms by which IgA functions. On this basis we propose how IgA may contribute to the establishment and maintenance of beneficial interactions with the microbiota.
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Affiliation(s)
- Oliver Pabst
- 0000 0001 0728 696Xgrid.1957.aInstitute of Molecular Medicine, RWTH Aachen University, Aachen, Germany
| | - Emma Slack
- 0000 0001 2156 2780grid.5801.cInstitute of Food, Nutrition and Health, Department of Health Sciences and Technology, ETH Zürich, Zürich, Switzerland
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17
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18
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Zhao Y, Uduman M, Siu JHY, Tull TJ, Sanderson JD, Wu YCB, Zhou JQ, Petrov N, Ellis R, Todd K, Chavele KM, Guesdon W, Vossenkamper A, Jassem W, D'Cruz DP, Fear DJ, John S, Scheel-Toellner D, Hopkins C, Moreno E, Woodman NL, Ciccarelli F, Heck S, Kleinstein SH, Bemark M, Spencer J. Spatiotemporal segregation of human marginal zone and memory B cell populations in lymphoid tissue. Nat Commun 2018; 9:3857. [PMID: 30242242 PMCID: PMC6155012 DOI: 10.1038/s41467-018-06089-1] [Citation(s) in RCA: 63] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Accepted: 08/17/2018] [Indexed: 01/19/2023] Open
Abstract
Human memory B cells and marginal zone (MZ) B cells share common features such as the expression of CD27 and somatic mutations in their IGHV and BCL6 genes, but the relationship between them is controversial. Here, we show phenotypic progression within lymphoid tissues as MZ B cells emerge from the mature naïve B cell pool via a precursor CD27-CD45RBMEM55+ population distant from memory cells. By imaging mass cytometry, we find that MZ B cells and memory B cells occupy different microanatomical niches in organised gut lymphoid tissues. Both populations disseminate widely between distant lymphoid tissues and blood, and both diversify their IGHV repertoire in gut germinal centres (GC), but nevertheless remain largely clonally separate. MZ B cells are therefore not developmentally contiguous with or analogous to classical memory B cells despite their shared ability to transit through GC, where somatic mutations are acquired.
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Affiliation(s)
- Yuan Zhao
- School of Immunology and Microbial Sciences, King's College London, Guy's Campus, London, SE1 9RT, UK
| | - Mohamed Uduman
- Department of Pathology, Yale University School of Medicine, New Haven, CT, 06511, USA
| | | | - Thomas J Tull
- School of Immunology and Microbial Sciences, King's College London, Guy's Campus, London, SE1 9RT, UK
| | - Jeremy D Sanderson
- School of Immunology and Microbial Sciences, King's College London, Guy's Campus, London, SE1 9RT, UK
| | - Yu-Chang Bryan Wu
- Randall Division of Cell and Molecular Biophysics, King's College London, London, SE1 1UL, UK
| | - Julian Q Zhou
- Interdepartmental Program in Computational Biology and Bioinformatics, Yale University, New Haven, CT, 06511, USA
| | - Nedyalko Petrov
- Biomedical Research Centre, Guy's and St. Thomas' NHS Trust, London, SE1 9RT, UK
| | - Richard Ellis
- Biomedical Research Centre, Guy's and St. Thomas' NHS Trust, London, SE1 9RT, UK
| | - Katrina Todd
- Biomedical Research Centre, Guy's and St. Thomas' NHS Trust, London, SE1 9RT, UK
| | - Konstantia-Maria Chavele
- School of Immunology and Microbial Sciences, King's College London, Guy's Campus, London, SE1 9RT, UK
| | - William Guesdon
- School of Immunology and Microbial Sciences, King's College London, Guy's Campus, London, SE1 9RT, UK
| | - Anna Vossenkamper
- Barts & The London School of Medicine and Dentistry, Blizard Institute, Whitechapel, London, E1 2AT, UK
| | - Wayel Jassem
- Liver Transplant Unit, Institute of Liver Studies, King's College Hospital, Denmark Hill, London, SE5 9NT, UK
| | - David P D'Cruz
- School of Immunology and Microbial Sciences, King's College London, Guy's Campus, London, SE1 9RT, UK
| | - David J Fear
- School of Immunology and Microbial Sciences, King's College London, Guy's Campus, London, SE1 9RT, UK
| | - Susan John
- School of Immunology and Microbial Sciences, King's College London, Guy's Campus, London, SE1 9RT, UK
| | - Dagmar Scheel-Toellner
- Institute of Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Birmingham, B15 2TT, UK
| | - Claire Hopkins
- School of Immunology and Microbial Sciences, King's College London, Guy's Campus, London, SE1 9RT, UK
| | - Estefania Moreno
- Barts & The London School of Medicine and Dentistry, Blizard Institute, Whitechapel, London, E1 2AT, UK
| | - Natalie L Woodman
- School of Cancer Sciences, King's College London, Guy's Campus, London, SE1 9RT, UK
| | - Francesca Ciccarelli
- School of Cancer Sciences, King's College London, Guy's Campus, London, SE1 9RT, UK
| | - Susanne Heck
- Biomedical Research Centre, Guy's and St. Thomas' NHS Trust, London, SE1 9RT, UK
| | - Steven H Kleinstein
- Department of Pathology, Yale University School of Medicine, New Haven, CT, 06511, USA.
- Interdepartmental Program in Computational Biology and Bioinformatics, Yale University, New Haven, CT, 06511, USA.
- Department of Immunobiology, Yale University School of Medicine, New Haven, CT, 06511, USA.
| | - Mats Bemark
- Mucosal Immunobiology and Vaccine Center (MIVAC), Department of Microbiology and Immunology, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, SE 405 30, Gothenburg, Sweden.
| | - Jo Spencer
- School of Immunology and Microbial Sciences, King's College London, Guy's Campus, London, SE1 9RT, UK.
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19
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Lycke NY, Bemark M. The regulation of gut mucosal IgA B-cell responses: recent developments. Mucosal Immunol 2017; 10:1361-1374. [PMID: 28745325 DOI: 10.1038/mi.2017.62] [Citation(s) in RCA: 115] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Accepted: 05/20/2017] [Indexed: 02/04/2023]
Abstract
The majority of activated B cells differentiate into IgA plasma cells, with the gut being the largest producer of immunoglobulin in the body. Secretory IgA antibodies have numerous critical functions of which protection against infections and the role for establishing a healthy microbiota appear most important. Expanding our knowledge of the regulation of IgA B-cell responses and how effective mucosal vaccines can be designed are of critical importance. Here we discuss recent developments in the field that shed light on the uniqueness and complexity of mucosal IgA responses and the control of protective IgA responses in the gut, specifically.
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Affiliation(s)
- N Y Lycke
- Department of Microbiology and Immunology, Mucosal Immunobiology and Vaccine Center, Institute of Biomedicine, University of Gothenburg, Gothenburg, Sweden
| | - M Bemark
- Department of Microbiology and Immunology, Mucosal Immunobiology and Vaccine Center, Institute of Biomedicine, University of Gothenburg, Gothenburg, Sweden
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20
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Akhi R, Wang C, Kyrklund M, Kummu O, Turunen SP, Hyvärinen K, Kullaa A, Salo T, Pussinen PJ, Hörkkö S. Cross-reactive saliva IgA antibodies to oxidized LDL and periodontal pathogens in humans. J Clin Periodontol 2017; 44:682-691. [PMID: 28548243 DOI: 10.1111/jcpe.12748] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/20/2017] [Indexed: 02/02/2023]
Abstract
AIM Oxidized low-density lipoproteins (oxLDL) are formed as a result of lipid peroxidation and are highly immunogenic and proatherogenic. In this study, saliva antibodies binding to oxLDL, Porphyromonas gingivalis (Pg) and Aggregatibacter actinomycetemcomitans (Aa) were characterized and their cross-reactivity was evaluated. MATERIALS AND METHODS Resting and stimulated saliva samples were collected from 36 healthy adults (mean age 26 years). Saliva IgA, IgG and IgM autoantibody levels to copper oxidized LDL (CuOx-LDL) and malondialdehyde acetaldehyde-modified LDL (MAA-LDL) were determined with chemiluminescence immunoassay. RESULTS Saliva IgA and IgG antibodies binding to MAA-LDL and CuOx-LDL were detected in all samples and they were associated with the saliva levels of IgA and IgG to P. gingivalis and A. actinomycetemcomitans. Competitive immunoassay showed that saliva antibodies to MAA-LDL cross-reacted specifically with P. gingivalis. The autoantibody levels to oxLDL in saliva were not associated with the autoantibody levels to oxLDL in plasma or with saliva apolipoprotein B 100 levels. CONCLUSIONS Saliva contains IgA and IgG binding to oxLDL, which showed cross-reactive properties with the periodontal pathogens Porphyromonas gingivalis (P.g). The data suggest that secretory IgA to P.g may participate in immune reactions involved in LDL oxidation through molecular mimicry.
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Affiliation(s)
- Ramin Akhi
- Medical Microbiology and Immunology, Research Unit of Biomedicine, University of Oulu, Oulu, Finland.,Medical Research Center, Oulu University Hospital and University of Oulu, Oulu, Finland.,Nordlab, Oulu University Hospital, Oulu, Finland.,Research Unit of Oral Health Sciences, University of Oulu, Oulu, Finland
| | - Chunguang Wang
- Medical Microbiology and Immunology, Research Unit of Biomedicine, University of Oulu, Oulu, Finland.,Medical Research Center, Oulu University Hospital and University of Oulu, Oulu, Finland.,Nordlab, Oulu University Hospital, Oulu, Finland
| | - Mikael Kyrklund
- Medical Microbiology and Immunology, Research Unit of Biomedicine, University of Oulu, Oulu, Finland.,Medical Research Center, Oulu University Hospital and University of Oulu, Oulu, Finland.,Nordlab, Oulu University Hospital, Oulu, Finland
| | - Outi Kummu
- Medical Microbiology and Immunology, Research Unit of Biomedicine, University of Oulu, Oulu, Finland.,Medical Research Center, Oulu University Hospital and University of Oulu, Oulu, Finland.,Nordlab, Oulu University Hospital, Oulu, Finland
| | - Sini Pauliina Turunen
- Medical Microbiology and Immunology, Research Unit of Biomedicine, University of Oulu, Oulu, Finland.,Medical Research Center, Oulu University Hospital and University of Oulu, Oulu, Finland.,Research Programs Unit, Genome-Scale Biology, University of Helsinki, Helsinki, Finland
| | - Kati Hyvärinen
- Oral and Maxillofacial Diseases, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Arja Kullaa
- Research Unit of Oral Health Sciences, University of Oulu, Oulu, Finland
| | - Tuula Salo
- Medical Research Center, Oulu University Hospital and University of Oulu, Oulu, Finland.,Cancer Research and Translational Medicine Research Unit, University of Oulu, Oulu, Finland
| | - Pirkko J Pussinen
- Oral and Maxillofacial Diseases, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Sohvi Hörkkö
- Medical Microbiology and Immunology, Research Unit of Biomedicine, University of Oulu, Oulu, Finland.,Medical Research Center, Oulu University Hospital and University of Oulu, Oulu, Finland.,Nordlab, Oulu University Hospital, Oulu, Finland
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21
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Agace WW, McCoy KD. Regionalized Development and Maintenance of the Intestinal Adaptive Immune Landscape. Immunity 2017; 46:532-548. [PMID: 28423335 DOI: 10.1016/j.immuni.2017.04.004] [Citation(s) in RCA: 111] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Revised: 04/03/2017] [Accepted: 04/04/2017] [Indexed: 12/14/2022]
Abstract
The intestinal immune system has the daunting task of protecting us from pathogenic insults while limiting inflammatory responses against the resident commensal microbiota and providing tolerance to food antigens. This role is particularly impressive when one considers the vast mucosal surface and changing landscape that the intestinal immune system must monitor. In this review, we highlight regional differences in the development and composition of the adaptive immune landscape of the intestine and the impact of local intrinsic and environmental factors that shape this process. To conclude, we review the evidence for a critical window of opportunity for early-life exposures that affect immune development and alter disease susceptibility later in life.
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Affiliation(s)
- William W Agace
- Division of Immunology and Vaccinology, National Veterinary Institute, Technical University of Denmark (DTU), 2800 Kongens Lyngby, Denmark; Immunology Section, Department of Experimental Medical Science, Lund University, BMC D14, Sölvegatan 19, 221 84 Lund, Sweden.
| | - Kathy D McCoy
- Department of Physiology and Pharmacology and Calvin, Phoebe and Joan Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 4N1, Canada.
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22
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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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23
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Sehgal A, Kobayashi A, Donaldson DS, Mabbott NA. c-Rel is dispensable for the differentiation and functional maturation of M cells in the follicle-associated epithelium. Immunobiology 2016; 222:316-326. [PMID: 27663963 PMCID: PMC5152706 DOI: 10.1016/j.imbio.2016.09.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Revised: 08/30/2016] [Accepted: 09/17/2016] [Indexed: 01/22/2023]
Abstract
M cells reside within the follicle-associated epithelium (FAE) overlying the gut-associated lymphoid tissues. These unique phagocytic epithelial cells enable the mucosal immune system to sample antigens within the lumen of the intestine. The differentiation of M cells from uncommitted precursors in the FAE is dependent on the production of receptor activator of nuclear factor-κB ligand (RANKL) by subepithelial stromal cells. The ligation of a variety of cell surface receptors activates the nuclear factor-κB (NF-κB) family of transcription factors which in-turn induce the transcription of multiple target genes. RANKL-stimulation can stimulate the nuclear translocation of the NF-κB subunit c-Rel. We therefore used c-Rel-deficient mice to determine whether the differentiation and functional maturation of M cells in the Peyer's patches was dependent on c-Rel. Our data show that c-Rel-deficiency does not influence the expression of RANKL or RANK in Peyer's patches, or the induction of M-cell differentiation in the FAE. RANKL-stimulation in the differentiating M cells induces the expression of SpiB which is essential for their subsequent maturation. However, SpiB expression in the FAE was also unaffected in the absence of c-Rel. As a consequence, the functional maturation of M cells was not impaired in the Peyer's patches of c-Rel-deficient mice. Although our data showed that the specific expression of CCL20 and ubiquitin D in the FAE was not impeded in the absence of c-Rel, the expression of ubiquitin D was dramatically reduced in the B cell-follicles of c-Rel-deficient mice. Coincident with this, we also observed that the status of follicular dendritic cells in the B cell-follicles was dramatically reduced in Peyer's patches from c-Rel-deficient mice. Taken together, our data show that c-Rel is dispensable for the RANKL-mediated differentiation and functional maturation of M cells.
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Affiliation(s)
- Anuj Sehgal
- The Roslin Institute and Royal (Dick) School of Veterinary Sciences, University of Edinburgh, Easter Bush, Midlothian, EH25 9RG, UK
| | - Atsushi Kobayashi
- Laboratory of Comparative Pathology, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan
| | - David S Donaldson
- The Roslin Institute and Royal (Dick) School of Veterinary Sciences, University of Edinburgh, Easter Bush, Midlothian, EH25 9RG, UK
| | - Neil A Mabbott
- The Roslin Institute and Royal (Dick) School of Veterinary Sciences, University of Edinburgh, Easter Bush, Midlothian, EH25 9RG, UK.
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24
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Späth PJ, Schneider C, von Gunten S. Clinical Use and Therapeutic Potential of IVIG/SCIG, Plasma-Derived IgA or IgM, and Other Alternative Immunoglobulin Preparations. Arch Immunol Ther Exp (Warsz) 2016; 65:215-231. [DOI: 10.1007/s00005-016-0422-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Accepted: 08/31/2016] [Indexed: 12/22/2022]
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25
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The Distribution of SIgA and IgG Antibody-Secreting Cells in the Small Intestine of Bactrian Camels (Camelus bactrianus) of Different Ages. PLoS One 2016; 11:e0156635. [PMID: 27249417 PMCID: PMC4889134 DOI: 10.1371/journal.pone.0156635] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2016] [Accepted: 05/17/2016] [Indexed: 12/12/2022] Open
Abstract
Secretory immunoglobulin A (SIgA) and immunoglobulin G (IgG) antibody-secreting cells (ASCs) are two important cell types in the mucosal immune system. This study aimed to explore the distribution of these ASC populations in the small intestine of Bactrian camels of different ages. Twenty-four Alashan Bactrian camels were divided into the following four age groups: young (1–2 years), pubertal (3–5 years), middle-aged (6–16 years) and old (17–20 years). SIgA and IgG ASCs in the intestinal mucosa lamina propria (LP) were observed and analyzed using immunohistochemcal techniques. The results from all age groups show that both SIgA and IgG ASCs were diffusely distributed in the intestinal LP, and some cells aggregated around the crypts. Moreover, the densities of the two ASC populations gradually increased from the duodenum to the jejunum and then decreased in the ileum. Meanwhile, there were more SIgA ASCs than IgG ASCs in the duodenum, jejunum, and ileum, and these differences were significant in the young and pubertal groups (P<0.05). In addition, the SIgA and IgG ASC densities increased from the young to the pubertal period, peaked at puberty, and then gradually decreased with age. The results demonstrate that the SIgA and IgG ASC distributions help to form two immunoglobulin barriers in the intestinal mucosa to provide full protection, helping to maintain homeostasis. These findings also underscore the importance of researching the development and degeneration of intestinal mucosal immunity in Bactrian camels.
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26
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The function and affinity maturation of HIV-1 gp120-specific monoclonal antibodies derived from colostral B cells. Mucosal Immunol 2016; 9:414-27. [PMID: 26242599 PMCID: PMC4744153 DOI: 10.1038/mi.2015.70] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2015] [Accepted: 06/23/2015] [Indexed: 02/06/2023]
Abstract
Despite the risk of transmitting HIV-1, mothers in resource-poor areas are encouraged to breastfeed their infants because of beneficial immunologic and nutritional factors in milk. Interestingly, in the absence of antiretroviral prophylaxis, the overwhelming majority of HIV-1-exposed, breastfeeding infants are naturally protected from infection. To understand the role of HIV-1 envelope (Env)-specific antibodies in breast milk in natural protection against infant virus transmission, we produced 19 HIV-1 Env-specific monoclonal antibodies (mAbs) isolated from colostrum B cells of HIV-1-infected mothers and investigated their specificity, evolution, and anti-HIV-1 functions. Despite the previously reported genetic compartmentalization and gp120-specific bias of colostrum HIV Env-specific B cells, the colostrum Env-specific mAbs described here demonstrated a broad range of gp120 epitope specificities and functions, including inhibition of epithelial cell binding and dendritic cell-mediated virus transfer, neutralization, and antibody-dependent cellular cytotoxicity. We also identified divergent patterns of colostrum Env-specific B-cell lineage evolution with respect to crossreactivity to gastrointestinal commensal bacteria, indicating that commensal bacterial antigens play a role in shaping the local breast milk immunoglobulin G (IgG) repertoire. Maternal vaccine strategies to specifically target this breast milk B-cell population may be necessary to achieve safe breastfeeding for all HIV-1-exposed infants.
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27
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Runtsch MC, Hu R, Alexander M, Wallace J, Kagele D, Petersen C, Valentine JF, Welker NC, Bronner MP, Chen X, Smith DP, Ajami NJ, Petrosino JF, Round JL, O'Connell RM. MicroRNA-146a constrains multiple parameters of intestinal immunity and increases susceptibility to DSS colitis. Oncotarget 2015; 6:28556-72. [PMID: 26456940 PMCID: PMC4745677 DOI: 10.18632/oncotarget.5597] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Accepted: 08/22/2015] [Indexed: 12/12/2022] Open
Abstract
Host-microbial interactions within the mammalian intestines must be properly regulated in order to promote host health and limit disease. Because the microbiota provide constant immunological signals to intestinal tissues, a variety of regulatory mechanisms have evolved to ensure proper immune responses to maintain homeostasis. However, many of the genes that comprise these regulatory pathways, including immune-modulating microRNAs (miRNAs), have not yet been identified or studied in the context of intestinal homeostasis. Here, we investigated the role of microRNA-146a (miR-146a) in regulating intestinal immunity and barrier function and found that this miRNA is expressed in a variety of gut tissues in adult mice. By comparing intestinal gene expression in WT and miR-146a-/- mice, we demonstrate that miR-146a represses a subset of gut barrier and inflammatory genes all within a network of immune-related signaling pathways. We also found that miR-146a restricts the expansion of intestinal T cell populations, including Th17, Tregs, and Tfh cells. GC B cells, Tfh ICOS expression, and the production of luminal IgA were also reduced by miR-146a in the gut. Consistent with an enhanced intestinal barrier, we found that miR-146a-/- mice are resistant to DSS-induced colitis, a model of Ulcerative Colitis (UC), and this correlated with elevated colonic miR-146a expression in human UC patients. Taken together, our data describe a role for miR-146a in constraining intestinal barrier function, a process that alters gut homeostasis and enhances at least some forms of intestinal disease in mice.
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Affiliation(s)
- Marah C. Runtsch
- Department of Pathology, University of Utah, Salt Lake City, UT, USA
| | - Ruozhen Hu
- Department of Pathology, University of Utah, Salt Lake City, UT, USA
| | | | - Jared Wallace
- Department of Pathology, University of Utah, Salt Lake City, UT, USA
| | - Dominique Kagele
- Department of Pathology, University of Utah, Salt Lake City, UT, USA
| | - Charisse Petersen
- Department of Pathology, University of Utah, Salt Lake City, UT, USA
| | - John F. Valentine
- Department of Medicine, Division of Gastroenterology, University of Utah, Salt Lake City, UT, USA
| | - Noah C. Welker
- Department of Pathology, University of Utah and ARUP Laboratories, Salt Lake City, UT, USA
| | - Mary P. Bronner
- Department of Pathology, University of Utah and ARUP Laboratories, Salt Lake City, UT, USA
| | - Xinjian Chen
- Department of Pathology, University of Utah, Salt Lake City, UT, USA
| | - Daniel P. Smith
- The Alkek Center for Metagenomics and Microbiome Research, Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX, USA
| | - Nadim J. Ajami
- The Alkek Center for Metagenomics and Microbiome Research, Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX, USA
| | - Joseph F. Petrosino
- The Alkek Center for Metagenomics and Microbiome Research, Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX, USA
| | - June L. Round
- Department of Pathology, University of Utah, Salt Lake City, UT, USA
| | - Ryan M. O'Connell
- Department of Pathology, University of Utah, Salt Lake City, UT, USA
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28
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The bilateral responsiveness between intestinal microbes and IgA. Trends Immunol 2015; 36:460-70. [PMID: 26169256 DOI: 10.1016/j.it.2015.06.006] [Citation(s) in RCA: 99] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2015] [Revised: 06/01/2015] [Accepted: 06/19/2015] [Indexed: 12/30/2022]
Abstract
The immune system has developed strategies to maintain a homeostatic relationship with the resident microbiota. IgA is central in holding this relationship, as the most dominant immunoglobulin isotype at the mucosal surface of the intestine. Recent studies report a role for IgA in shaping the composition of the intestinal microbiota and exploit strategies to characterise IgA-binding bacteria for their inflammatory potential. We review these findings here, and place them in context of the current understanding of the range of microorganisms that contribute to the IgA repertoire and the pathways that determine the quality of the IgA response. We examine why only certain intestinal microbes are coated with IgA, and discuss how understanding the determinants of this specific responsiveness may provide insight into diseases associated with dysbiosis.
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29
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Diversification of memory B cells drives the continuous adaptation of secretory antibodies to gut microbiota. Nat Immunol 2015; 16:880-8. [DOI: 10.1038/ni.3213] [Citation(s) in RCA: 153] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Accepted: 05/31/2015] [Indexed: 02/07/2023]
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Snir O, Mesin L, Gidoni M, Lundin KEA, Yaari G, Sollid LM. Analysis of celiac disease autoreactive gut plasma cells and their corresponding memory compartment in peripheral blood using high-throughput sequencing. THE JOURNAL OF IMMUNOLOGY 2015; 194:5703-12. [PMID: 25972486 DOI: 10.4049/jimmunol.1402611] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2014] [Accepted: 04/17/2015] [Indexed: 11/19/2022]
Abstract
Autoreactive IgA plasma cells (PCs) specific for the enzyme transglutaminase 2 (TG2) are abundant in the small intestine of patients with active celiac disease (CD), and their number drops in patients treated by dietary gluten elimination. Little is known about their characteristics and their role in the disease. In this study, using high-throughput sequencing of the IgH V region (IGHV) genes, we have studied features of TG2-specific PCs and their related B cell clones in peripheral blood. We found that TG2-specific PCs from both untreated and treated patients have acquired lower number of somatic hypermutation and used focused IGHV repertoire with overrepresentation of the IGHV3-48, IGHV4-59, IGHV5-10-1, and IGHV5-51 gene segments. Furthermore, these PCs were clonally expanded and showed signs of affinity maturation. Lineage trees demonstrated shared clones between gut PCs and blood memory B cells, primarily IgAs. Some trees also involved IgG cells, suggesting that anti-TG2 IgA and IgG responses are related. Similarly to TG2-specific PCs, clonally related memory IgA B cells of blood showed lower mutation rates with biased usage of IGHV3-48 and IGHV5-51. Such memory cells were rare in peripheral blood, yet detectable in most patients assessed by production of anti-TG2 Abs in vitro following stimulation of cells from patients who had been on a long-term gluten-free diet. Thus, the Ab response to TG2 in CD, while maintaining its IGHV gene usage, is dynamically regulated in response to gluten exposure with a low degree of maintenance at both PC and memory B cell levels in patients in remission.
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Affiliation(s)
- Omri Snir
- Centre for Immune Regulation and Department of Immunology, University of Oslo and Oslo University Hospital, 0372 Oslo, Norway
| | - Luka Mesin
- Centre for Immune Regulation and Department of Immunology, University of Oslo and Oslo University Hospital, 0372 Oslo, Norway
| | - Moriah Gidoni
- Bioengineering Program, Faculty of Engineering, Bar-Ilan University, Ramt Gan 52900, Israel; and
| | - Knut E A Lundin
- Centre for Immune Regulation and Department of Immunology, University of Oslo and Oslo University Hospital, 0372 Oslo, Norway; Department of Gastroenterology, Oslo University Hospital-Rikshospitalet, 0372 Oslo, Norway
| | - Gur Yaari
- Bioengineering Program, Faculty of Engineering, Bar-Ilan University, Ramt Gan 52900, Israel; and
| | - Ludvig M Sollid
- Centre for Immune Regulation and Department of Immunology, University of Oslo and Oslo University Hospital, 0372 Oslo, Norway;
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Bemark M. Translating transitions - how to decipher peripheral human B cell development. J Biomed Res 2015; 29:264-84. [PMID: 26243514 PMCID: PMC4547376 DOI: 10.7555/jbr.29.20150035] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Accepted: 02/10/2015] [Indexed: 01/05/2023] Open
Abstract
During the last two decades our understanding of human B cell differentiation has developed considerably. Our understanding of the human B cell compartment has advanced from a point where essentially all assays were based on the presence or not of class-switched antibodies to a level where a substantial diversity is appreciated among the cells involved. Several consecutive transitional stages that newly formed IgM expressing B cells go through after they leave the bone marrow, but before they are fully mature, have been described, and a significant complexity is also acknowledged within the IgM expressing and class-switched memory B cell compartments. It is possible to isolate plasma blasts in blood to follow the formation of plasma cells during immune responses, and the importance and uniqueness of the mucosal IgA system is now much more appreciated. Current data suggest the presence of at least one lineage of human innate-like B cells akin to B1 and/or marginal zone B cells in mice. In addition, regulatory B cells with the ability to produce IL-10 have been identified. Clinically, B cell depletion therapy is used for a broad range of conditions. The ability to define different human B cell subtypes using flow cytometry has therefore started to come into clinical use, but as our understanding of human B cell development further progresses, B cell subtype analysis will be of increasing importance in diagnosis, to measure the effect of immune therapy and to understand the underlying causes for diseases. In this review the diversity of human B cells will be discussed, with special focus on current data regarding their phenotypes and functions.
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Affiliation(s)
- Mats Bemark
- Department of Clinical Immunology and Transfusion Medicine, Sahlgrenska University hospital, SE 413 45 Gothenburg, Sweden.,Mucosal Immunobiology and Vaccine Center (MIVAC), Department of Microbiology and Immunology, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, SE 405 30 Gothenburg, Sweden.
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Mabbott NA, Kobayashi A, Sehgal A, Bradford BM, Pattison M, Donaldson DS. Aging and the mucosal immune system in the intestine. Biogerontology 2015; 16:133-45. [PMID: 24705962 DOI: 10.1007/s10522-014-9498-z] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2013] [Accepted: 03/24/2014] [Indexed: 02/07/2023]
Abstract
Bacterial and viral infections of the gastrointestinal tract are more common in the elderly and represent a major cause of morbidity and mortality. The mucosal immune system provides the first line of defence against pathogens acquired by ingestion and inhalation, but its function is adversely affected in the elderly. This aging-related decline in the immune function is termed immunosenescence and is associated with diminished abilities to generate protective immunity, reduced vaccine efficacy, increased incidence of cancer, inflammation and autoimmunity, and the impaired ability to generate tolerance to harmless antigens. In this review we describe our current understanding of the effects immunosenescence has on the innate and adaptive arms of the mucosal immune system in the intestine. Current estimates suggest that by the year 2050 up to 40% of the UK population will be over 65 years old, bringing with it important health challenges. A thorough understanding of the mechanisms that contribute to the development of immunosenescence is therefore crucial to help identify novel approaches to improve mucosal immunity in the elderly.
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Affiliation(s)
- Neil A Mabbott
- The Roslin Institute & Royal (Dick) School of Veterinary Sciences, University of Edinburgh, Easter Bush, Midlothian, EH25 9RG, UK,
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33
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Lycke N, Bemark M, Spencer J. Mucosal B Cell Differentiation and Regulation. Mucosal Immunol 2015. [DOI: 10.1016/b978-0-12-415847-4.00033-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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34
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Fagarasan S, Macpherson AJ. The Regulation of IgA Production. Mucosal Immunol 2015. [DOI: 10.1016/b978-0-12-415847-4.00023-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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35
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Inomata M, Kusano T, Etoh T, Akagi T, Shibata T, Ueda Y, Tojigamori M, Shiroshita H, Noguchi T, Shiraishi N, Kitano S. Comparing incidence of enterocolitis after laparoscopic and open low anterior resection for stage II/III rectal cancer. Asian J Endosc Surg 2014; 7:214-21. [PMID: 24690093 DOI: 10.1111/ases.12100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/28/2013] [Revised: 02/04/2014] [Accepted: 03/02/2014] [Indexed: 11/30/2022]
Abstract
INTRODUCTION We recently observed an increased incidence of severe enterocolitis following laparoscopic low anterior resection (LAR) in some patients with stage II/III rectal cancer. This study aimed to examine the influence of laparoscopic LAR on postoperative enterocolitis compared with open LAR for Stage II/III rectal cancer. METHODS From April 2002 to March 2012, we evaluated 65 patients with stage II/III cancer of the upper or lower rectum who underwent LAR. Among these, 27 patients underwent open LAR and 38 underwent laparoscopic LAR. First, we compared short-term outcomes between the two groups. Next, we evaluated the incidence of postoperative enterocolitis in the laparoscopic LAR group. The clinicopathological factors were examined by univariate and odds ratio (OR) analysis. RESULTS Univariate analysis revealed significant differences in the occupancy rate, tumor location, depth of tumor invasion, operative time, amount of intraoperative blood loss, and postoperative enterocolitis between the laparoscopic and open groups. Postoperative enterocolitis developed in 6 of 38 patients (15.8%) in the laparoscopic group and in no patient in the open group. The occurrence of postoperative enterocolitis was significantly associated with BMI (≥28 kg/m(2) ), operative time, and wound infection in the laparoscopic LAR group (OR: 0.11, 95% confidence interval: 0.044-0.280, P < 0.05; OR: 1.40, 95% confidence interval: 1.068-1.835, P < 0.05; and OR: 15.0, 95% confidence interval, 1.752-128.310, P < 0.05, respectively). CONCLUSION Postoperative enterocolitis occurred more frequently after laparoscopic LAR than after open LAR in patients with stage II/III rectal cancer. Clinical management in the perioperative period of laparoscopic LAR is necessary to prevent postoperative enterocolitis in obese patients and those with a prolonged operative time.
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Affiliation(s)
- Masafumi Inomata
- Department of Gastroenterological and Pediatric Surgery, Oita University Faculty of Medicine, Oita, Japan
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36
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Lécuyer E, Rakotobe S, Lengliné-Garnier H, Lebreton C, Picard M, Juste C, Fritzen R, Eberl G, McCoy KD, Macpherson AJ, Reynaud CA, Cerf-Bensussan N, Gaboriau-Routhiau V. Segmented filamentous bacterium uses secondary and tertiary lymphoid tissues to induce gut IgA and specific T helper 17 cell responses. Immunity 2014; 40:608-20. [PMID: 24745335 DOI: 10.1016/j.immuni.2014.03.009] [Citation(s) in RCA: 238] [Impact Index Per Article: 23.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2013] [Accepted: 01/29/2014] [Indexed: 12/12/2022]
Abstract
Segmented filamentous bacterium (SFB) is a symbiont that drives postnatal maturation of gut adaptive immune responses. In contrast to nonpathogenic E. coli, SFB stimulated vigorous development of Peyer's patches germinal centers but paradoxically induced only a low frequency of specific immunoglobulin A (IgA)-secreting cells with delayed accumulation of somatic mutations. Moreover, blocking Peyer's patch development abolished IgA responses to E. coli, but not to SFB. Indeed, SFB stimulated the postnatal development of isolated lymphoid follicles and tertiary lymphoid tissue, which substituted for Peyer's patches as inductive sites for intestinal IgA and SFB-specific T helper 17 (Th17) cell responses. Strikingly, in mice depleted of gut organized lymphoid tissue, SFB still induced a substantial but nonspecific intestinal Th17 cell response. These results demonstrate that SFB has the remarkable capacity to induce and stimulate multiple types of intestinal lymphoid tissues that cooperate to generate potent IgA and Th17 cell responses displaying only limited target specificity.
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Affiliation(s)
- Emelyne Lécuyer
- INSERM UMR1163, Laboratory of Intestinal Immunity; Université Paris Descartes-Sorbonne Paris Cité and Institut Imagine, 75015 Paris, France
| | - Sabine Rakotobe
- INSERM UMR1163, Laboratory of Intestinal Immunity; Université Paris Descartes-Sorbonne Paris Cité and Institut Imagine, 75015 Paris, France; INRA Micalis UMR1319, 78350 Jouy-en-Josas, France
| | - Hélène Lengliné-Garnier
- INSERM UMR1163, Laboratory of Intestinal Immunity; Université Paris Descartes-Sorbonne Paris Cité and Institut Imagine, 75015 Paris, France; AP-HP, Department of Pediatric Gastroenterology, Hôpital Necker, 75015 Paris, France
| | - Corinne Lebreton
- INSERM UMR1163, Laboratory of Intestinal Immunity; Université Paris Descartes-Sorbonne Paris Cité and Institut Imagine, 75015 Paris, France
| | - Marion Picard
- INSERM UMR1163, Laboratory of Intestinal Immunity; Université Paris Descartes-Sorbonne Paris Cité and Institut Imagine, 75015 Paris, France
| | | | - Rémi Fritzen
- Université Paris Descartes-Sorbonne Paris Cité and Institut Imagine, 75015 Paris, France; INSERM UMR 1151, Institut Necker-Enfants Malades, Université Paris Descartes- Sorbonne Paris Cité, 75014 Paris, France
| | - Gérard Eberl
- Institut Pasteur, Lymphoid Tissue Development Unit, 75015 Paris, France
| | - Kathy D McCoy
- Maurice Müller Laboratories, Universitätsklinik für Viszerale Chirurgie und Medizin (UVCM), University of Bern, 3008 Bern, Switzerland
| | - Andrew J Macpherson
- Maurice Müller Laboratories, Universitätsklinik für Viszerale Chirurgie und Medizin (UVCM), University of Bern, 3008 Bern, Switzerland
| | - Claude-Agnès Reynaud
- Université Paris Descartes-Sorbonne Paris Cité and Institut Imagine, 75015 Paris, France; INSERM UMR 1151, Institut Necker-Enfants Malades, Université Paris Descartes- Sorbonne Paris Cité, 75014 Paris, France
| | - Nadine Cerf-Bensussan
- INSERM UMR1163, Laboratory of Intestinal Immunity; Université Paris Descartes-Sorbonne Paris Cité and Institut Imagine, 75015 Paris, France.
| | - Valérie Gaboriau-Routhiau
- INSERM UMR1163, Laboratory of Intestinal Immunity; Université Paris Descartes-Sorbonne Paris Cité and Institut Imagine, 75015 Paris, France; INRA Micalis UMR1319, 78350 Jouy-en-Josas, France.
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37
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Lycke NY. IgA B Cell Responses to Gut Mucosal Antigens: Do We Know it all? Front Immunol 2013; 4:368. [PMID: 24312091 PMCID: PMC3826092 DOI: 10.3389/fimmu.2013.00368] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2013] [Accepted: 10/28/2013] [Indexed: 11/30/2022] Open
Affiliation(s)
- Nils Y Lycke
- Department of Microbiology and Immunology, Institute of Biomedicine, University of Gothenburg , Gothenburg , Sweden
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38
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Abstract
The gastrointestinal tract is heavily colonized with commensal microbes with the concentration of bacteria increasing longitudinally down the length of the intestine. Bacteria are also spatially distributed transversely from the epithelial surface to the intestinal lumen with the inner mucus layer normally void of bacteria. Maintenance of this equilibrium is extremely important for human health and, as the dominant immunoglobulin at mucosal sites, IgA influences mutualism between the host and its normal microbiota. In this review we focus on the links between immune and microbial geography of the mammalian intestinal tract.
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39
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Vossenkämper A, Blair PA, Safinia N, Fraser LD, Das L, Sanders TJ, Stagg AJ, Sanderson JD, Taylor K, Chang F, Choong LM, D'Cruz DP, Macdonald TT, Lombardi G, Spencer J. A role for gut-associated lymphoid tissue in shaping the human B cell repertoire. ACTA ACUST UNITED AC 2013; 210:1665-74. [PMID: 23940259 PMCID: PMC3754866 DOI: 10.1084/jem.20122465] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Transitional 2 B cells home to gut-associated lymphoid tissue and present an activated phenotype in healthy subjects, but gut immune compartments are depleted in SLE. We have tracked the fate of immature human B cells at a critical stage in their development when the mature B cell repertoire is shaped. We show that a major subset of bone marrow emigrant immature human B cells, the transitional 2 (T2) B cells, homes to gut-associated lymphoid tissue (GALT) and that most T2 B cells isolated from human GALT are activated. Activation in GALT is a previously unknown potential fate for immature human B cells. The process of maturation from immature transitional B cell through to mature naive B cell includes the removal of autoreactive cells from the developing repertoire, a process which is known to fail in systemic lupus erythematosus (SLE). We observe that immature B cells in SLE are poorly equipped to access the gut and that gut immune compartments are depleted in SLE. Thus, activation of immature B cells in GALT may function as a checkpoint that protects against autoimmunity. In healthy individuals, this pathway may be involved in generating the vast population of IgA plasma cells and also the enigmatic marginal zone B cell subset that is poorly understood in humans.
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Affiliation(s)
- Anna Vossenkämper
- Blizard Institute and 2 Digestive Diseases Clinical Academic Unit, Barts and the London School of Medicine and Dentistry, Whitechapel, London, England, UK.
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40
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Corthésy B. Multi-faceted functions of secretory IgA at mucosal surfaces. Front Immunol 2013; 4:185. [PMID: 23874333 PMCID: PMC3709412 DOI: 10.3389/fimmu.2013.00185] [Citation(s) in RCA: 364] [Impact Index Per Article: 33.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2013] [Accepted: 06/24/2013] [Indexed: 01/06/2023] Open
Abstract
Secretory IgA (SIgA) plays an important role in the protection and homeostatic regulation of intestinal, respiratory, and urogenital mucosal epithelia separating the outside environment from the inside of the body. This primary function of SIgA is referred to as immune exclusion, a process that limits the access of numerous microorganisms and mucosal antigens to these thin and vulnerable mucosal barriers. SIgA has been shown to be involved in avoiding opportunistic pathogens to enter and disseminate in the systemic compartment, as well as tightly controlling the necessary symbiotic relationship existing between commensals and the host. Clearance by peristalsis appears thus as one of the numerous mechanisms whereby SIgA fulfills its function at mucosal surfaces. Sampling of antigen-SIgA complexes by microfold (M) cells, intimate contact occurring with Peyer’s patch dendritic cells (DC), down-regulation of inflammatory processes, modulation of epithelial, and DC responsiveness are some of the recently identified processes to which the contribution of SIgA has been underscored. This review aims at presenting, with emphasis at the biochemical level, how the molecular complexity of SIgA can serve these multiple and non-redundant modes of action.
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Affiliation(s)
- Blaise Corthésy
- R&D Laboratory, Department of Immunology and Allergy, University State Hospital Lausanne (CHUV) , Lausanne , Switzerland
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41
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Abstract
Controversy has arisen about the nature of circulating human CD20(+)CD27(+)CD43(+)CD70(-)CD69(-) B cells. Although originally described as being the human counterpart of murine B-1 B cells, some studies have raised the possibility that these might instead be plasmablasts. In this article, we have further characterized the putative B-1 cells and compared them directly with memory B cells and plasmablasts for several functional characteristics. Spontaneous antibody production of different isotypes as well as the induced production of antigen-specific antibodies after vaccination with a T-cell-dependent antigen did not reveal differences between the putative B-1 cells and genuine CD20(-) plasmablasts. Gene expression profiling of different B-cell subsets positioned the phenotype of putative B-1 cells closer to CD20(-) plasmablasts than to memory B cells. Moreover, putative B-1 cells could be differentiated into CD20(-) plasmablasts and plasma cells in vitro, supporting a pre-plasmablast phenotype. In conclusion, characterization of the putative B-1 cells revealed a functional phenotype and a gene expression profile that corresponds to cells that differentiate into CD20(-) plasmablasts. Our data offer perspectives for the investigation of differentiation of B cells into antibody secreting cells.
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Re-utilization of germinal centers in multiple Peyer's patches results in highly synchronized, oligoclonal, and affinity-matured gut IgA responses. Mucosal Immunol 2013; 6:122-35. [PMID: 22785230 DOI: 10.1038/mi.2012.56] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Whereas gut IgA responses to the microbiota may be multi-centered and diverse, little is known about IgA responses to T-cell-dependent antigens following oral immunizations. Using a novel approach, gut IgA responses to oral hapten (4-hydroxy-3-nitrophenyl)acetyl-cholera toxin (NP-CT) conjugates were followed at the cellular and molecular level. Surprisingly, these responses were highly synchronized, strongly oligoclonal, and dominated by affinity matured cells. Extensive lineage trees revealed clonal relationships between NP-specific IgA cells in gut inductive and effector sites, suggesting expansion of the same B-cell clone in multiple Peyer's patches (PPs). Adoptive transfer experiments showed that this was achieved through re-utilization of already existing germinal centers (GCs) in multiple PPs by previously activated GC GL7(+) B cells, provided oral NP-CT was given before cell transfer. Taken together, these results explain why repeated oral immunizations are mandatory for an effective oral vaccine.
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Abstract
Because Peyer's patches (PP) are the main inductive sites for gut IgA responses we have focused this review on what we know about the function of PP germinal centers (GC). The vast majority of IgA gene sequences in the gut lamina propria (LP) are heavily mutated arguing for an origin in GC. Because PP GC formation is dependent on the presence of CD4 T cells, we speculate that all IgA responses in the normal gut are directly or indirectly T cell-dependent (TD). We hypothesize that the CD4 T cell involvement in gut IgA responses against the microbiota is different from that in systemic responses since cognate T-B cell interactions appear not to be required. In the absence of cognate interactions the function of CD4 follicular helper T cells (Tfh) in PP GC is unclear. However, production of IL-21 and IL-6 is more pronounced than in peripheral lymph nodes. Importantly, we discuss how multiple PP are involved in generating specific IgA responses to TD antigens given orally. Recently we found that oral immunization with NP-hapten conjugated to cholera toxin (NP-CT) stimulated a strong highly synchronized, oligoclonal and affinity matured IgA response. This was achieved through re-utilization of GC in multiple PP as GC IgA B cells emigrated into already established GC. Clonally related B cells were present in both inductive and effector lymphoid tissues in the gut and clonal trees involving multiple PP could be constructed in individual mice. Through adoptive transfer of B1-8(hi) NP-specific B cells we demonstrated that GL7(+) PP B cells could enter into pre-existing GC in PP, a process that was antigen-dependent but did not to require cognate Tfh interactions. Finally, we discuss the role of PP GC for the generation of memory B cells and long-lived plasma cells in the light of contrasting findings regarding IgA memory development to colonizing commensal bacteria versus that to oral immunization with enteropathogens or TD antigens.
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Affiliation(s)
- Nils Y Lycke
- Mucosal Immunobiology and Vaccines Center, Department of Microbiology and Immunology, Institute of Biomedicine, University of Gothenburg Gothenburg, Sweden
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45
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Abstract
The intestinal mucosa contains the largest population of antibody-secreting plasma cells in the body, and in humans several grams of secretory immunoglobulin A (SIgA) are released into the intestine each day. In the gut lumen, SIgA serves as a first-line barrier that protects the epithelium from pathogens and toxins. Recently, next-generation sequencing has revolutionized our understanding of the nature of the intestinal microbiota and has also shed new light on the important roles of SIgA in the regulation of host-commensal homeostasis. Here, I discuss pathways of IgA induction in the context of SIgA specificity and function.
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Affiliation(s)
- Oliver Pabst
- Institute of Immunology, Hannover Medical School, Carl-Neuberg Strae 1, 30625 Hannover, Germany.
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Mesin L, Sollid LM, Di Niro R. The intestinal B-cell response in celiac disease. Front Immunol 2012; 3:313. [PMID: 23060888 PMCID: PMC3463893 DOI: 10.3389/fimmu.2012.00313] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2012] [Accepted: 09/18/2012] [Indexed: 12/19/2022] Open
Abstract
The function of intestinal immunity is to provide protection toward pathogens while preserving the composition of the microflora and tolerance to orally fed nutrients. This is achieved via a number of tightly regulated mechanisms including production of IgA antibodies by intestinal plasma cells. Celiac disease is a common gut disorder caused by a dysfunctional immune regulation as signified, among other features, by a massive intestinal IgA autoantibody response. Here we review the current knowledge of this B-cell response and how it is induced, and we discuss key questions to be addressed in future research.
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Affiliation(s)
- Luka Mesin
- Centre for Immune Regulation, Department of Immunology, Oslo University Hospital-Rikshospitalet, University of Oslo, Oslo, Norway
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Spencer J, Klavinskis LS, Fraser LD. The human intestinal IgA response; burning questions. Front Immunol 2012; 3:108. [PMID: 22593756 PMCID: PMC3349913 DOI: 10.3389/fimmu.2012.00108] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2012] [Accepted: 04/17/2012] [Indexed: 12/14/2022] Open
Abstract
The title of this special topic invites us to identify areas in the field of IgA biology that are uncertain or in need of clarification. The inductive phase of the human intestinal IgA response has been a controversial area for some years. Therefore, to structure this review, we have identified key questions that are debated in this field. We have provided explanations of the origins of the uncertainties and have provided our own reasoned answers to the questions we pose.
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Affiliation(s)
- Jo Spencer
- Peter Gorer Department of Immunobiology, King’s College London School of Medicine at Guy’s King’s College and St. Thomas’ HospitalsLondon, UK
| | - Linda S. Klavinskis
- Peter Gorer Department of Immunobiology, King’s College London School of Medicine at Guy’s King’s College and St. Thomas’ HospitalsLondon, UK
| | - Louise D. Fraser
- Peter Gorer Department of Immunobiology, King’s College London School of Medicine at Guy’s King’s College and St. Thomas’ HospitalsLondon, UK
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Macpherson AJ, Geuking MB, Slack E, Hapfelmeier S, McCoy KD. The habitat, double life, citizenship, and forgetfulness of IgA. Immunol Rev 2012; 245:132-46. [PMID: 22168417 DOI: 10.1111/j.1600-065x.2011.01072.x] [Citation(s) in RCA: 103] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Immunoglobulin A (IgA) is the main secretory immunoglobulin of mucous membranes and is powerfully induced by the presence of commensal microbes in the intestine. B cells undergo class switch recombination to IgA in the mucosa-associated lymphoid tissues, particularly mesenteric lymph nodes (MLNs) and Peyer's patches, through both T-dependent and T-independent pathways. IgA B cells primed in the mucosa traffic from the intestinal lymphoid structures, initially through the lymphatics and then join the bloodstream, to home back to the intestinal mucosa as IgA-secreting plasma cells. Once induced, anti-bacterial IgA can be extremely long-lived but is replaced if there is induction of additional IgA specificities by other microbes. The mucosal immune system is anatomically separated from the systemic immune system by the MLNs, which act as a firewall to prevent penetration of live intestinal bacteria to systemic sites. Dendritic cells sample intestinal bacteria and induce B cells to switch to IgA. In contrast, intestinal macrophages are adept at killing extracellular bacteria and are able to clear bacteria that have crossed the mucus and epithelial barriers. There is both a continuum between innate and adaptive immune mechanisms and compartmentalization of the mucosal immune system from systemic immunity that function to preserve host microbial mutualism.
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Affiliation(s)
- Andrew J Macpherson
- Mucosal Immunology Lab, Maurice Müller Laboratories, University Clinic for Visceral Surgery and Medicine, University of Bern, Bern, Switzerland.
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Macpherson AJ, Geuking MB, McCoy KD. Homeland security: IgA immunity at the frontiers of the body. Trends Immunol 2012; 33:160-7. [PMID: 22410243 DOI: 10.1016/j.it.2012.02.002] [Citation(s) in RCA: 106] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2011] [Revised: 02/02/2012] [Accepted: 02/07/2012] [Indexed: 12/30/2022]
Abstract
IgA is the most abundant immunoglobulin produced in mammals, and is mostly secreted across mucous membranes. At these frontiers, which are constantly assaulted by pathogenic and commensal microbes, IgA provides part of a layered system of immune protection. In this review, we describe how IgA induction occurs through both T-dependent and T-independent mechanisms, and how IgA is generated against the prodigious load of commensal microbes after mucosal dendritic cells (DCs) have sampled a tiny fraction of the microbial consortia in the intestinal lumen. To function in this hostile environment, IgA must be induced behind the 'firewall' of the mesenteric lymph nodes to generate responses that integrate microbial stimuli, rather than the classical prime-boost effects characteristic of systemic immunity.
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Affiliation(s)
- Andrew J Macpherson
- Maurice Müller Laboratories, DKF, Universitätsklinik für Viszerale Chirurgie und Medizin, University Hospital (Inselspital), University of Bern, Bern, Switzerland.
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Bemark M, Boysen P, Lycke NY. Induction of gut IgA production through T cell-dependent and T cell-independent pathways. Ann N Y Acad Sci 2012; 1247:97-116. [PMID: 22260403 DOI: 10.1111/j.1749-6632.2011.06378.x] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The gut immune system protects against mucosal pathogens, maintains a mutualistic relationship with the microbiota, and establishes tolerance against food antigens. This requires a balance between immune effector responses and induction of tolerance. Disturbances of this strictly regulated balance can lead to infections or the development inflammatory diseases and allergies. Production of secretory IgA is a unique effector function at mucosal surfaces, and basal mechanisms regulating IgA production have been the focus of much recent research. These investigations have aimed at understanding how long-term IgA-mediated mucosal immunity can best be achieved by oral or sublingual vaccination, or at analyzing the relationship between IgA production, the composition of the gut microbiota, and protection from allergies and autoimmunity. This research has lead to a better understanding of the IgA system; but at the same time seemingly conflicting data have been generated. Here, we discuss how gut IgA production is controlled, with special focus on how differences between T cell-dependent and T cell-independent IgA production may explain some of these discrepancies.
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Affiliation(s)
- Mats Bemark
- Department of Microbiology and Immunology, Mucosal Immunobiology and Vaccine Center, Institute of Biomedicine, University of Gothenburg, Gothenburg, Sweden.
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