151
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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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152
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153
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Chorny A, Cerutti A. Regulation and Function of Mucosal IgA and IgD. Mucosal Immunol 2015. [DOI: 10.1016/b978-0-12-415847-4.00032-x] [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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154
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Old questions, new tools: does next-generation sequencing hold the key to unraveling intestinal B-cell responses? Mucosal Immunol 2015; 8:29-37. [PMID: 25389035 DOI: 10.1038/mi.2014.103] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2014] [Accepted: 09/18/2014] [Indexed: 02/04/2023]
Abstract
Analysis of the intestinal B-cell system and properties of immunoglobulin A, the main antibody isotype produced in the gut, has dominated the rise of mucosal immunology as a discipline. Seminal work established concepts describing the induction, transport, and function of mucosal antibodies. Still, open questions remain and we lack a comprehensive view of how the various sites and pathways of immunoglobulin A induction are integrated to respond to gut antigens. Next-generation sequencing (NGS) offers a novel approach to study B-cell responses, which might substantially enhance our tool box to answer key questions in the field and to take the next steps toward therapeutic exploitation of the mucosal B-cell system. In this review we discuss the potential, challenges, and emerging solutions for gut B-cell repertoire analysis by NGS.
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155
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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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156
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Chai JN, Zhou YW, Hsieh CS. T cells and intestinal commensal bacteria--ignorance, rejection, and acceptance. FEBS Lett 2014; 588:4167-75. [PMID: 24997344 DOI: 10.1016/j.febslet.2014.06.040] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2014] [Revised: 06/23/2014] [Accepted: 06/24/2014] [Indexed: 02/01/2023]
Abstract
Trillions of commensal bacteria cohabit our bodies to mutual benefit. In the past several years, it has become clear that the adaptive immune system is not ignorant of intestinal commensal bacteria, but is constantly interacting with them. For T cells, the response to commensal bacteria does not appear uniform, as certain commensal bacterial species appear to trigger effector T cells to reject and control them, whereas other species elicit Foxp3(+) regulatory T (Treg) cells to accept and be tolerant of them. Here, we review our current knowledge of T cell differentiation in response to commensal bacteria, and how this process leads to immune homeostasis in the intestine.
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Affiliation(s)
- Jiani N Chai
- Department of Medicine, Division of Rheumatology, Washington University School of Medicine, St. Louis, MO 63132, United States
| | - You W Zhou
- Department of Medicine, Division of Rheumatology, Washington University School of Medicine, St. Louis, MO 63132, United States
| | - Chyi-Song Hsieh
- Department of Medicine, Division of Rheumatology, Washington University School of Medicine, St. Louis, MO 63132, United States.
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157
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Briney BS, Willis JR, Finn JA, McKinney BA, Crowe JE. Tissue-specific expressed antibody variable gene repertoires. PLoS One 2014; 9:e100839. [PMID: 24956460 PMCID: PMC4067404 DOI: 10.1371/journal.pone.0100839] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2013] [Accepted: 05/30/2014] [Indexed: 01/05/2023] Open
Abstract
Recent developments in genetic technologies allow deep analysis of the sequence diversity of immune repertoires, but little work has been reported on the architecture of immune repertoires in mucosal tissues. Antibodies are the key to prevention of infections at the mucosal surface, but it is currently unclear whether the B cell repertoire at mucosal surfaces reflects the dominant antibodies found in the systemic compartment or whether mucosal tissues harbor unique repertoires. We examined the expressed antibody variable gene repertoires from 10 different human tissues using RNA samples derived from a large number of individuals. The results revealed that mucosal tissues such as stomach, intestine and lung possess unique antibody gene repertoires that differed substantially from those found in lymphoid tissues or peripheral blood. Mutation frequency analysis of mucosal tissue repertoires revealed that they were highly mutated, with little evidence for the presence of naïve B cells, in contrast to blood. Mucosal tissue repertoires possessed longer heavy chain complementarity determining region 3 loops than lymphoid tissue repertoires. We also noted a large increase in frequency of both insertions and deletions in the small intestine antibody repertoire. These data suggest that mucosal immune repertoires are distinct in many ways from the systemic compartment.
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Affiliation(s)
- Bryan S. Briney
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - Jordan R. Willis
- The Chemical and Physical Biology Program, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Jessica A. Finn
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - Brett A. McKinney
- Tandy School of Computer Science and Department of Mathematics, University of Tulsa, Tulsa, Oklahoma, United States of America
| | - James E. Crowe
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
- The Vanderbilt Vaccine Center, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
- * E-mail:
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158
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Diagnostic potential of monoclonal antibodies specific to the unique O-antigen of multidrug-resistant epidemic Escherichia coli clone ST131-O25b:H4. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2014; 21:930-9. [PMID: 24789798 DOI: 10.1128/cvi.00685-13] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The Escherichia coli lineage sequence type 131 (ST131)-O25b:H4 is a globally spread multidrug-resistant clone responsible for a great proportion of extraintestinal infections. Driven by the significant medical needs associated with this successful pathogenic lineage, we generated murine monoclonal antibodies (MAbs) against its lipopolysaccharide (LPS) O25b antigen in order to develop quick diagnostic tests. Murine monoclonal antibodies were generated by immunizing mice with whole killed nonencapsulated ST131-O25b E. coli cells and screening hybridoma supernatants for binding to purified LPS molecules obtained from an E. coli ST131-O25b clinical isolate. The MAbs selected for further study bound to the surface of live E. coli O25b strains irrespective of the capsular type expressed, while they did not bind to bacteria or purified LPS from other serotypes, including the related classical O25 antigen (O25a). Using these specific MAbs, we developed a latex bead-based agglutination assay that has greater specificity and is quicker and simpler than the currently available typing methods. The high specificities of these MAbs can be explained by the novel structure of the O25b repeating unit elucidated in this article. Based on comparative analysis by nuclear magnetic resonance (NMR) and mass spectrometry, the N-acetyl-fucose in the O25a O-antigen had been replaced by O-acetyl-rhamnose in the O25b repeating unit. The genetic determinants responsible for this structural variation were identified by aligning the corresponding genetic loci and were confirmed by trans-complementation of a rough mutant by the subserotype-specific fragments of the rfb operons.
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159
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Tiburzy B, Kulkarni U, Hauser AE, Abram M, Manz RA. Plasma cells in immunopathology: concepts and therapeutic strategies. Semin Immunopathol 2014; 36:277-88. [PMID: 24740168 DOI: 10.1007/s00281-014-0426-8] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2013] [Accepted: 04/01/2014] [Indexed: 12/12/2022]
Abstract
Plasma cells are terminally differentiated B cells that secrete antibodies, important for immune protection, but also contribute to any allergic and autoimmune disease. There is increasing evidence that plasma cell populations exhibit a considerable degree of heterogeneity with respect to their immunophenotype, migration behavior, lifetime, and susceptibility to immunosuppressive drugs. Pathogenic long-lived plasma cells are refractory to existing therapies. In contrast, short-lived plasma cells can be depleted by steroids and cytostatic drugs. Therefore, long-lived plasma cells are responsible for therapy-resistant autoantibodies and resemble a challenge for the therapy of antibody-mediated autoimmune diseases. Both lifetime and therapy resistance of plasma cells are supported by factors produced within their microenviromental niches. Current results suggest that plasma cell differentiation and survival factors such as IL-6 also signal via mammalian miRNAs within the plasma cell to modulate downstream transcription factors. Recent evidence also suggests that plasma cells and/or their immediate precursors (plasmablasts) can produce important cytokines and act as antigen-presenting cells, exhibiting so far underestimated roles in immune regulation and bone homeostasis. Here, we provide an overview on plasma cell biology and discuss exciting, experimental, and potential therapeutic approaches to eliminate pathogenic plasma cells.
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Affiliation(s)
- Benjamin Tiburzy
- Institute for Systemic Inflammation Research (ISEF), University of Lübeck, Ratzeburger Allee 160, 23538, Lübeck, Germany
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160
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Buckner CM, Moir S, Kardava L, Ho J, Santich BH, Kim LJY, Funk EK, Nelson AK, Winckler B, Chairez CL, Theobald-Whiting NL, Anaya-O'Brien S, Alimchandani M, Quezado MM, Yao MD, Kovacs JA, Chun TW, Fauci AS, Malech HL, De Ravin SS. CXCR4/IgG-expressing plasma cells are associated with human gastrointestinal tissue inflammation. J Allergy Clin Immunol 2013; 133:1676-85.e5. [PMID: 24373354 DOI: 10.1016/j.jaci.2013.10.050] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2013] [Revised: 09/16/2013] [Accepted: 10/14/2013] [Indexed: 12/30/2022]
Abstract
BACKGROUND We previously reported abnormalities in circulating B cells in patients with chronic granulomatous disease (CGD) and those with HIV infection. Gastrointestinal complications are common to both diseases and likely involve perturbation of immune cells, including plasma cells (PCs). IgA is the most abundant immunoglobulin in the human body, with roles in protection and maintenance of intestinal homeostasis. IgA is produced primarily by PCs residing in mucosal tissues that are also thought to circulate in the blood. OBJECTIVE We sought to characterize and compare PCs in patients with infectious (HIV) and noninfectious (CGD and Crohn disease) diseases that have been associated with intestinal inflammation. METHODS Phenotypic and transcriptional analyses were performed on cells isolated from the blood and colon. RESULTS IgA-secreting CCR10-expressing PCs predominated in the guts of healthy subjects, whereas in patients with HIV, CGD, and Crohn disease, there was a significant increase in the proportion of IgG-secreting PCs. Where intestinal inflammation was present, IgG-secreting PCs expressed reduced levels of CCR10 and increased levels of CXCR4. The intensity of CXCR4 expression correlated with the frequency of IgG-expressing PCs and the frequency of CXCR4(+)/IgG(+) PCs was associated with the severity of intestinal inflammatory disease yet distinct from PCs and plasmablasts circulating in the blood. CONCLUSIONS These findings suggest that regardless of the underlying disease, the presence of CXCR4(+)/IgG(+) PCs in the gut is a strong yet localized indicator of intestinal inflammation. Furthermore, our findings suggest that CXCR4(+)/IgG(+) PCs might play a role in immune cell homeostasis during inflammatory processes of the gut.
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Affiliation(s)
- Clarisa M Buckner
- Laboratory of Immunoregulation, National Institute of Allergy and Infectious Diseases, Bethesda, Md
| | - Susan Moir
- Laboratory of Immunoregulation, National Institute of Allergy and Infectious Diseases, Bethesda, Md.
| | - Lela Kardava
- Laboratory of Immunoregulation, National Institute of Allergy and Infectious Diseases, Bethesda, Md
| | - Jason Ho
- Laboratory of Immunoregulation, National Institute of Allergy and Infectious Diseases, Bethesda, Md
| | - Brian H Santich
- Laboratory of Immunoregulation, National Institute of Allergy and Infectious Diseases, Bethesda, Md
| | - Leo Jin Young Kim
- Laboratory of Immunoregulation, National Institute of Allergy and Infectious Diseases, Bethesda, Md
| | - Emily K Funk
- Laboratory of Immunoregulation, National Institute of Allergy and Infectious Diseases, Bethesda, Md
| | - Amy K Nelson
- Laboratory of Immunoregulation, National Institute of Allergy and Infectious Diseases, Bethesda, Md
| | - Britanny Winckler
- Laboratory of Host Defenses, National Institute of Allergy and Infectious Diseases, Bethesda, Md
| | - Cheryl L Chairez
- Laboratory of Immunoregulation, National Institute of Allergy and Infectious Diseases, Bethesda, Md
| | - Narda L Theobald-Whiting
- Laboratory of Host Defenses, National Institute of Allergy and Infectious Diseases, Bethesda, Md
| | - Sandra Anaya-O'Brien
- Laboratory of Host Defenses, National Institute of Allergy and Infectious Diseases, Bethesda, Md
| | | | - Martha M Quezado
- Laboratory of Pathology, National Cancer Institute, Bethesda, Md
| | - Michael D Yao
- Laboratory of Host Defenses, National Institute of Allergy and Infectious Diseases, Bethesda, Md
| | - Joseph A Kovacs
- Critical Care Medicine, National Institutes of Health Clinical Center, Bethesda, Md
| | - Tae-Wook Chun
- Laboratory of Immunoregulation, National Institute of Allergy and Infectious Diseases, Bethesda, Md
| | - Anthony S Fauci
- Laboratory of Immunoregulation, National Institute of Allergy and Infectious Diseases, Bethesda, Md
| | - Harry L Malech
- Laboratory of Host Defenses, National Institute of Allergy and Infectious Diseases, Bethesda, Md
| | - Suk See De Ravin
- Laboratory of Host Defenses, National Institute of Allergy and Infectious Diseases, Bethesda, Md.
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161
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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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162
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Sedykh MA, Buneva VN, Nevinsky GA. Polyreactivity of natural antibodies: Exchange by HL-fragments. BIOCHEMISTRY (MOSCOW) 2013; 78:1305-1320. [DOI: 10.1134/s0006297913120018] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/30/2023]
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163
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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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164
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Dimitrov JD, Planchais C, Roumenina LT, Vassilev TL, Kaveri SV, Lacroix-Desmazes S. Antibody polyreactivity in health and disease: statu variabilis. THE JOURNAL OF IMMUNOLOGY 2013; 191:993-9. [PMID: 23873158 DOI: 10.4049/jimmunol.1300880] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
An Ab molecule or a BCR that is able to bind multiple structurally unrelated Ags is defined as polyreactive. Polyreactive Abs and BCRs constitute an important part of immune repertoires under physiological conditions and may play essential roles in immune defense and in the maintenance of immune homeostasis. In this review, we integrate and discuss different findings that reveal the indispensable role of Ag-binding polyreactivity in the immune system. First, we describe the functional and molecular characteristics of polyreactive Abs. The following part of the review concentrates on the biological roles attributed to polyreactive Abs and to polyreactive BCRs. Finally, we discuss recent studies that link Ig polyreactivity with distinct pathological conditions.
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Affiliation(s)
- Jordan D Dimitrov
- INSERM, Unité 872, Centre de Recherche des Cordeliers, 75006 Paris, France.
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165
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Tarlinton D, Good-Jacobson K. Diversity among memory B cells: origin, consequences, and utility. Science 2013; 341:1205-11. [PMID: 24031013 DOI: 10.1126/science.1241146] [Citation(s) in RCA: 151] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Immunological memory is the residuum of a successful immune response that in the B cell lineage comprises long-lived plasma cells and long-lived memory B cells. It is apparent that distinct classes of memory B cells exist, distinguishable by, among other things, immunoglobulin isotype, location, and passage through the germinal center. Some of this variation is due to the nature of the antigen, and some appears to be inherent to the process of forming memory. Here, we consider the heterogeneity in development and phenotype of memory B cells and whether particular functions are partitioned into distinct subsets. We consider also how understanding the details of generating memory may provide opportunities to develop better, functionally targeted vaccines.
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Affiliation(s)
- David Tarlinton
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia.
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166
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Brandtzaeg P. Immune aspects of breast milk: an overview. HANDBOOK OF DIETARY AND NUTRITIONAL ASPECTS OF HUMAN BREAST MILK 2013. [DOI: 10.3920/978-90-8686-764-6_3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- P. Brandtzaeg
- Laboratory for Immunohistochemistry and Immunopathology (LIIPAT), Centre for Immune Regulation (CIR), University of Oslo and Department of Pathology, Oslo University Hospital, Rikshospitalet, Oslo, P.O. Box 4950 Nydalen, 0424 Oslo, Norway
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167
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Fairfax KC, Everts B, Smith AM, Pearce EJ. Regulation of the development of the hepatic B cell compartment during Schistosoma mansoni infection. THE JOURNAL OF IMMUNOLOGY 2013; 191:4202-10. [PMID: 24038090 DOI: 10.4049/jimmunol.1301357] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
During infection with the helminth parasite Schistosoma mansoni, Ab regulates hepatic inflammation, and local production of Ig in the liver appears to play a role in this process. Exploring the development of the B cell response during infection, we found that parasite-specific IgG1-secreting plasma cells appeared first in the hepatic and mesenteric lymph nodes (LNs) and then at later times in the spleen, liver, and bone marrow. The LN B cell population peaked between weeks 10 and 12 of infection, and then contracted at a time that coincided with the expansion of the hepatic IgG1(+) B cell compartment, suggesting that B cells migrate from LNs to liver. CXCL9 and -16 expression in the liver increased during the time frame of B cell recruitment. Expression of the CXCL16 receptor CXCR6 was increased on B cells within the hepatic LNs, but not the mesenteric LNs. CXCR3, the receptor for CXCL9, was broadly expressed on IgG1(+) B cells in LNs and liver during infection. Increased hepatic expression of CXCL9 and -16 failed to occur if the IL-10R was blocked in vivo, an intervention associated with decreased liver B cell infiltration and the development of severe disease. Hepatic LN IgG1(+) cells migrated toward CXCL9 and -16 in vitro and to the liver in a pertussis toxin-sensitive fashion. Our data suggest that the coordinated expression of CXCL9 and -16 in the liver and of CXCR6 and CXCR3 on responding B cells within the hepatic LNs underpins establishment of the hepatic B cell infiltrate during chronic schistosomiasis.
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Affiliation(s)
- Keke C Fairfax
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110
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168
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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: 71] [Impact Index Per Article: 6.5] [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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169
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Brandtzaeg P. Secretory IgA: Designed for Anti-Microbial Defense. Front Immunol 2013; 4:222. [PMID: 23964273 PMCID: PMC3734371 DOI: 10.3389/fimmu.2013.00222] [Citation(s) in RCA: 213] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2013] [Accepted: 07/16/2013] [Indexed: 01/30/2023] Open
Abstract
Prevention of infections by vaccination remains a compelling goal to improve public health. Mucosal vaccines would make immunization procedures easier, be better suited for mass administration, and most efficiently induce immune exclusion - a term coined for non-inflammatory antibody shielding of internal body surfaces, mediated principally by secretory immunoglobulin A (SIgA). The exported antibodies are polymeric, mainly IgA dimers (pIgA), produced by local plasma cells (PCs) stimulated by antigens that target the mucose. SIgA was early shown to be complexed with an epithelial glycoprotein - the secretory component (SC). A common SC-dependent transport mechanism for pIgA and pentameric IgM was then proposed, implying that membrane SC acts as a receptor, now usually called the polymeric Ig receptor (pIgR). From the basolateral surface, pIg-pIgR complexes are taken up by endocytosis and then extruded into the lumen after apical cleavage of the receptor - bound SC having stabilizing and innate functions in the secretory antibodies. Mice deficient for pIgR show that this is the only receptor responsible for epithelial export of IgA and IgM. These knockout mice show a variety of defects in their mucosal defense and changes in their intestinal microbiota. In the gut, induction of B-cells occurs in gut-associated lymphoid tissue, particularly the Peyer's patches and isolated lymphoid follicles, but also in mesenteric lymph nodes. PC differentiation is accomplished in the lamina propria to which the activated memory/effector B-cells home. The airways also receive such cells from nasopharynx-associated lymphoid tissue but by different homing receptors. This compartmentalization is a challenge for mucosal vaccination, as are the mechanisms used by the mucosal immune system to discriminate between commensal symbionts (mutualism), pathobionts, and overt pathogens (elimination).
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Affiliation(s)
- Per Brandtzaeg
- Laboratory for Immunohistochemistry and Immunopathology (LIIPAT), Centre for Immune Regulation (CIR), University of Oslo, Oslo, Norway
- Department of Pathology, Oslo University Hospital Rikshospitalet, Oslo, Norway
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170
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Nochi T, Denton PW, Wahl A, Garcia JV. Cryptopatches are essential for the development of human GALT. Cell Rep 2013; 3:1874-84. [PMID: 23791525 DOI: 10.1016/j.celrep.2013.05.037] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Revised: 03/14/2013] [Accepted: 05/22/2013] [Indexed: 12/19/2022] Open
Abstract
Abnormal gut-associated lymphoid tissue (GALT) in humans is associated with infectious and autoimmune diseases, which cause dysfunction of the gastrointestinal (GI) tract immune system. To aid in investigating GALT pathologies in vivo, we bioengineered a human-mouse chimeric model characterized by the development of human GALT structures originating in mouse cryptopatches. This observation expands our mechanistic understanding of the role of cryptopatches in human GALT genesis and emphasizes the evolutionary conservation of this developmental process. Immunoglobulin class switching to IgA occurs in these GALT structures, leading to numerous human IgA-producing plasma cells throughout the intestinal lamina propria. CD4+ T cell depletion within GALT structures results from HIV infection, as it does in humans. This human-mouse chimeric model represents the most comprehensive experimental platform currently available for the study and for the preclinical testing of therapeutics designed to repair disease-damaged GALT.
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Affiliation(s)
- Tomonori Nochi
- Division of Infectious Diseases, Center for AIDS Research, University of North Carolina School of Medicine, Chapel Hill, NC 27599, USA
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171
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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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172
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Brandtzaeg P. Secretory immunity with special reference to the oral cavity. J Oral Microbiol 2013; 5:20401. [PMID: 23487566 PMCID: PMC3595421 DOI: 10.3402/jom.v5i0.20401] [Citation(s) in RCA: 185] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2013] [Revised: 01/29/2013] [Accepted: 02/15/2013] [Indexed: 11/14/2022] Open
Abstract
The two principal antibody classes present in saliva are secretory IgA (SIgA) and IgG; the former is produced as dimeric IgA by local plasma cells (PCs) in the stroma of salivary glands and is transported through secretory epithelia by the polymeric Ig receptor (pIgR), also named membrane secretory component (SC). Most IgG in saliva is derived from the blood circulation by passive leakage mainly via gingival crevicular epithelium, although some may be locally produced in the gingiva or salivary glands. Gut-associated lymphoid tissue (GALT) and nasopharynx-associated lymphoid tissue (NALT) do not contribute equally to the pool of memory/effector B cells differentiating to mucosal PCs throughout the body. Thus, enteric immunostimulation may not be the best way to activate the production of salivary IgA antibodies although the level of specific SIgA in saliva may still reflect an intestinal immune response after enteric immunization. It remains unknown whether the IgA response in submandibular/sublingual glands is better related to B-cell induction in GALT than the parotid response. Such disparity is suggested by the levels of IgA in submandibular secretions of AIDS patients, paralleling their highly upregulated intestinal IgA system, while the parotid IgA level is decreased. Parotid SIgA could more consistently be linked to immune induction in palatine tonsils/adenoids (human NALT) and cervical lymph nodes, as supported by the homing molecule profile observed after immune induction at these sites. Several other variables influence the levels of antibodies in salivary secretions. These include difficulties with reproducibility and standardization of immunoassays, the impact of flow rate, acute or chronic stress, protein loss during sample handling, and uncontrolled admixture of serum-derived IgG and monomeric IgA. Despite these problems, saliva is an easily accessible biological fluid with interesting scientific and clinical potentials.
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Affiliation(s)
- Per Brandtzaeg
- Per Brandtzaeg, Department of Pathology, Oslo University Hospital, Rikshospitalet, PO Box 4950 Oslo, NO-0424 Norway. Tel: +47-23072743, Fax: 47-23071511.
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173
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Abstract
There is currently a major focus on the role of the gut barrier function in balancing mucosal immune responses. Increased epithelial permeability for exogenous antigens is a crucial primary or secondary event in the pathogenesis of several disorders affecting body surfaces and beyond. The epithelial gate-keeper function is determined by the individual's age (e.g. preterm vs. term infant), diet, genetics, mucus composition, interactions between mast cells, nerves and neuropeptides, concurrent infection, the commensal microbiota and the epithelium-shielding effect of secretory IgA (SIgA) antibodies provided by breast milk or produced in the individual's gut. The integrity of the epithelial barrier furthermore depends on homeostatic regulatory mechanisms, including mucosal induction of regulatory T cells, where commensal microbiota-host interactions apparently play decisive roles. Thus, both extrinsic and intrinsic factors have been identified that may have an impact on the dynamics of the epithelial cell-cell junctions in the gut and thereby increase or reduce paracellular permeability. Experiments have shown that SIgA normally cooperates with innate defence factors to protect the epithelium and reinforce its barrier function. In the absence of SIgA commensal gut bacteria overstimulate innate epithelial immunity at the expense of expression of genes that regulate fat and carbohydrate metabolism, resulting in an epithelial gene signature that correlates with the development of lipid malabsorption. This shows that the intestinal epithelial barrier is a cross-road between defence and nutrition, and that SIgA is essential to keep the balance between these two functions.
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Affiliation(s)
- P. Brandtzaeg
- Laboratory for Immunohistochemistry and Immunopathology (LIIPAT), Centre for Immune Regulation (CIR), University of Oslo
- Department of Pathology, Oslo University Hospital, Rikshospitalet, P.O. Box 4950, 0424 Oslo, Norway
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174
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Mashoof S, Goodroe A, Du CC, Eubanks JO, Jacobs N, Steiner JM, Tizard I, Suchodolski JS, Criscitiello MF. Ancient T-independence of mucosal IgX/A: gut microbiota unaffected by larval thymectomy in Xenopus laevis. Mucosal Immunol 2013; 6:358-68. [PMID: 22929561 PMCID: PMC3514589 DOI: 10.1038/mi.2012.78] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Many studies address the influence of the gut microbiome on the immune system, but few dissect the effect of T cells on gut microbiota and mucosal responses. We have employed larval thymectomy in Xenopus to study the gut microbiota with and without the influence of T lymphocytes. Pyrosequencing of 16S ribosomal RNA genes was used to assess the relative abundance of bacterial groups present in the stomach, small and large intestine. Clostridiaceae was the most abundant family throughout the gut, while Bacteroidaceae, Enterobacteriaceae, and Flavobacteriaceae also were well represented. Unifrac analysis revealed no differences in microbiota distribution between thymectomized and unoperated frogs. This is consistent with immunization data showing that levels of the mucosal immunoglobulin IgX are not altered significantly by thymectomy. This study in Xenopus represents the oldest organisms that exhibit class switch to a mucosal isotype and is relevant to mammalian immunology, as IgA appears to have evolved from IgX based upon phylogeny, genomic synteny, and function.
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Affiliation(s)
- Sara Mashoof
- Comparative Immunogenetics Laboratory, Department of Veterinary Pathobiology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX 77843 USA
| | - Anna Goodroe
- Comparative Immunogenetics Laboratory, Department of Veterinary Pathobiology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX 77843 USA
| | - Christina C. Du
- Comparative Immunogenetics Laboratory, Department of Veterinary Pathobiology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX 77843 USA
| | - Jeannine O. Eubanks
- Comparative Immunogenetics Laboratory, Department of Veterinary Pathobiology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX 77843 USA
| | - Natalie Jacobs
- Comparative Immunogenetics Laboratory, Department of Veterinary Pathobiology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX 77843 USA
| | - Jörg M. Steiner
- Gastrointestinal Laboratory, Department of Small Animal Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX 77843 USA
| | - Ian Tizard
- Schubot Exotic Bird Health Center, Department of Veterinary Pathobiology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX 77843 USA
| | - Jan S. Suchodolski
- Gastrointestinal Laboratory, Department of Small Animal Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX 77843 USA
| | - Michael F. Criscitiello
- Comparative Immunogenetics Laboratory, Department of Veterinary Pathobiology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX 77843 USA
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175
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Abstract
The majority of lymphomas originate from B cells at the germinal center stage or beyond. Preferential selection of B cell clones by a limited set of antigens has been suggested to drive lymphoma development. However, little is known about the specificity of the antibodies expressed by lymphoma cells, and the role of antibody-specificity in lymphomagenesis remains elusive. Here, we describe a strategy to characterize the antibody reactivity of human B cells. The approach allows the unbiased characterization of the human antibody repertoire on a single cell level through the generation of recombinant monoclonal antibodies from single primary human B cells of defined origin. This protocol offers a detailed description of the method starting from the flow cytometric isolation of single human B cells, to the RT-PCR-based amplification of the expressed Igh, Igκ, and Igλ chain genes, and Ig gene expression vector cloning for the in vitro production of monoclonal antibodies. The strategy may be used to obtain information on the clonal evolution of B cell lymphomas by single cell Ig gene sequencing and on the antibody reactivity of human lymphoma B cells.
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Affiliation(s)
- Hedda Wardemann
- Research Group Molecular Immunology, Max Planck Institute for Infection Biology, Berlin, Germany.
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176
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Abstract
The natural human antibody response is a rich source of highly specific, neutralizing and self-tolerant therapeutic reagents. Recent advances have been made in isolating and characterizing monoclonal antibodies that are generated in response to natural infection or vaccination. Studies of the human antibody response have led to the discovery of crucial epitopes that could serve as new targets in vaccine design and in the creation of potentially powerful immunotherapies. With a focus on influenza virus and HIV, herein we summarize the technological tools used to identify and characterize human monoclonal antibodies and describe how these tools might be used to fight infectious diseases.
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177
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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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178
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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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179
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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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180
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Wu YCB, Kipling D, Dunn-Walters DK. Age-Related Changes in Human Peripheral Blood IGH Repertoire Following Vaccination. Front Immunol 2012; 3:193. [PMID: 22787463 PMCID: PMC3391689 DOI: 10.3389/fimmu.2012.00193] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2012] [Accepted: 06/20/2012] [Indexed: 01/10/2023] Open
Abstract
Immune protection against pulmonary infections, such as seasonal flu and invasive pneumonia, is severely attenuated with age, and vaccination regimes for the elderly people often fail to elicit effective immune response. We have previously shown that influenza and pneumococcal vaccine responses in the older population are significantly impaired in terms of serum antibody production, and have shown repertoire differences by CDR-H3 spectratype analysis. Here we report a detailed analysis of the B cell repertoire in response to vaccine, including a breakdown of sequences by class and subclass. Clustering analysis of high-throughput sequencing data enables us to visualize the response in terms of expansions of clonotypes, changes in CDR-H3 characteristics, and somatic hypermutation as well as identifying the commonly used IGH genes. We have highlighted a number of significant age-related changes in the B cell repertoire. Interestingly, in light of the fact that IgG is the most prevalent serum antibody and the most widely used as a correlate of protection, the most striking age-related differences are in the IgA response, with defects also seen in the IgM repertoire. In addition there is a skewing toward IgG2 in the IgG sequences of the older samples at all time points. This analysis illustrates the importance of antibody classes other than IgG and has highlighted a number of areas for future consideration in vaccine studies of the elderly.
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Affiliation(s)
- Yu-Chang Bryan Wu
- Department of Immunobiology, King's College London School of Medicine London, UK
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181
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Jones DD, DeIulio GA, Winslow GM. Antigen-driven induction of polyreactive IgM during intracellular bacterial infection. THE JOURNAL OF IMMUNOLOGY 2012; 189:1440-7. [PMID: 22730531 DOI: 10.4049/jimmunol.1200878] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Polyreactivity is well known as a property of natural IgM produced by B-1 cells. We demonstrate that polyreactive IgM is also generated during infection of mice with Ehrlichia muris, a tick-borne intracellular bacterial pathogen. The polyreactive IgM bound self and foreign Ags, including single-stranded and double-stranded DNA, insulin, thyroglobulin, LPS, influenza virus, and Borrelia burgdorferi. Production of polyreactive IgM during infection was Ag driven, not due to polyclonal B cell activation, as the majority of polyreactive IgM recognized ehrlichial Ag(s), including an immunodominant outer membrane protein. Monoclonal polyreactive IgM derived from T cell-independent spleen plasmablasts, which was germline-encoded, also bound cytoplasmic and nuclear Ags in HEp-2 cells. Polyreactive IgM protected immunocompromised mice against lethal bacterial challenge infection. Serum from human ehrlichiosis patients also contained polyreactive and self-reactive IgM. We propose that polyreactivity increases IgM efficacy during infection but may also exacerbate or mollify the response to foreign and self Ags.
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Affiliation(s)
- Derek D Jones
- Department of Biomedical Sciences, University at Albany, Albany, NY 12201, USA
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182
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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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183
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Kawamoto S, Tran TH, Maruya M, Suzuki K, Doi Y, Tsutsui Y, Kato LM, Fagarasan S. The inhibitory receptor PD-1 regulates IgA selection and bacterial composition in the gut. Science 2012; 336:485-9. [PMID: 22539724 DOI: 10.1126/science.1217718] [Citation(s) in RCA: 337] [Impact Index Per Article: 28.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Immunoglobulin A (IgA) is essential to maintain the symbiotic balance between gut bacterial communities and the host immune system. Here we provide evidence that the inhibitory co-receptor programmed cell death-1 (PD-1) regulates the gut microbiota through appropriate selection of IgA plasma cell repertoires. PD-1 deficiency generates an excess number of T follicular helper (T(FH)) cells with altered phenotypes, which results in dysregulated selection of IgA precursor cells in the germinal center of Peyer's patches. Consequently, the IgAs produced in PD-1-deficient mice have reduced bacteria-binding capacity, which causes alterations of microbial communities in the gut. Thus, PD-1 plays a critical role in regulation of antibody diversification required for the maintenance of intact mucosal barrier.
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Affiliation(s)
- Shimpei Kawamoto
- Laboratory for Mucosal Immunity, Research Center for Allergy and Immunology, RIKEN Yokohama, Tsurumi, Yokohama, Japan
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184
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Mouquet H, Nussenzweig MC. Polyreactive antibodies in adaptive immune responses to viruses. Cell Mol Life Sci 2012; 69:1435-45. [PMID: 22045557 PMCID: PMC11114792 DOI: 10.1007/s00018-011-0872-6] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2011] [Revised: 10/17/2011] [Accepted: 10/18/2011] [Indexed: 01/15/2023]
Abstract
B cells express immunoglobulins on their surface where they serve as antigen receptors. When secreted as antibodies, the same molecules are key elements of the humoral immune response against pathogens such as viruses. Although most antibodies are restricted to binding a specific antigen, some are polyreactive and have the ability to bind to several different ligands, usually with low affinity. Highly polyreactive antibodies are removed from the repertoire during B-cell development by physiologic tolerance mechanisms including deletion and receptor editing. However, a low level of antibody polyreactivity is tolerated and can confer additional binding properties to pathogen-specific antibodies. For example, high-affinity human antibodies to HIV are frequently polyreactive. Here we review the evidence suggesting that in the case of some pathogens like HIV, polyreactivity may confer a selective advantage to pathogen-specific antibodies.
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Affiliation(s)
- Hugo Mouquet
- Laboratory of Molecular Immunology, The Rockefeller University, New York City, NY 10021, USA.
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185
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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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186
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Fink K. Origin and Function of Circulating Plasmablasts during Acute Viral Infections. Front Immunol 2012; 3:78. [PMID: 22566959 PMCID: PMC3341968 DOI: 10.3389/fimmu.2012.00078] [Citation(s) in RCA: 133] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2012] [Accepted: 03/27/2012] [Indexed: 12/25/2022] Open
Abstract
Activated B cells proliferate and differentiate into antibody-producing cells, long-lived plasma cells, and memory B cells after immunization or infection. Repeated encounter of the same antigen triggers the rapid re-activation of pre-existing specific memory B cells, which then potentially enter new germinal center reactions and differentiate into short-lived plasmablasts or remain in the system as memory B cells. Short-lived class-switched IgG and IgA plasmablasts appear in the circulation transiently and the frequency of these cells can be remarkably high. The specificities and affinities of single plasmablasts in humans have been reported for several viral infections, so far most extensively for influenza and HIV. In general, the immunoglobulin variable regions of plasmablasts are highly mutated and diverse, suggesting that plasmablasts are derived from memory B cells, yet it is unclear which memory B cell subsets are activated and whether activated memory B cells adapt or mature before differentiation. This review summarizes what is known about the phenotype and the origin of human plasmablasts in the context of viral infections and whether these cells can be predictors of long-lived immunity.
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Affiliation(s)
- Katja Fink
- Singapore Immunology Network, Agency for Science, Technology and Research ASTAR Singapore
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187
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IgA synthesis: a form of functional immune adaptation extending beyond gut. Curr Opin Immunol 2012; 24:261-8. [PMID: 22503962 DOI: 10.1016/j.coi.2012.03.005] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2012] [Revised: 03/22/2012] [Accepted: 03/23/2012] [Indexed: 12/12/2022]
Abstract
Immunoglobulin A (IgA) is the most abundantly produced antibody isotype in mammals. The primary function of IgA is to maintain homeostasis at mucosal surfaces. IgA is generated in specialized gut associated lymphoid tissues (GALT) by T cell-dependent and T cell-independent mechanisms. Studies in mice have demonstrated that IgA diversification has an essential role in the regulation of gut microbiota. Aberrant bacterial growth, by activating innate and adaptive immune cells, has emerged as a risk factor for inflammatory diseases such as metabolic disorders and autoimmune diseases. Dynamic diversification of IgA shields bacterial antigens preventing inflammatory responses, but when IgA regulation is suboptimal aberrant bacterial growth and inflammation can ensue.
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188
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Human poly- and cross-reactive anti-viral antibodies and their impact on protection and pathology. Immunol Res 2012; 53:148-61. [DOI: 10.1007/s12026-012-8268-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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189
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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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190
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Abstract
PURPOSE OF REVIEW This article reviews the most recent publications on innate immunity in the small intestine. We will go over the innate immune receptors that act as sensors of microbial presence or cell injury, Paneth cells as the main epithelial cell type that secrete antimicrobial peptides, and mucosal production of immunoglobulin A (IgA). In addition, we will give an update on examples of imbalance of the innate immune response resulting in clinical disease with the most relevant example being Crohn's disease. RECENT FINDINGS Toll-like receptors (TLRs) are involved in B-cell homing to the intestine, rejection of small intestinal allografts, and recruitment of mast cells. The TLR adaptor Toll/interleukin-1 receptor domain-containing adapter-inducing interferon-β is necessary to activate innate immunity after Yersinia enterocolitica infection. Moreover, MyD88 is required to keep the intestinal microbiota under control and physically separated from the epithelium, and RegIIIγ is responsible for the bacterial segregation from the lining epithelial cells. In Crohn's disease, ATG16L1 T300A variant promotes a proinflammatory response; and miR-196 downregulates a protective immunity-related GTPase family M protein (IRGM) polymorphism leading to impaired clearance of adherent Escherichia coli in the intestine. SUMMARY The intestine is continuously exposed to dietary and microbial antigens. The host has to maintain intestinal homeostasis to keep the commensal and pathogenic bacteria under control. Some of the mechanisms to do so are by expression of innate immune receptors, production of antimicrobial peptides, secretion of IgA, or autophagy of intracellular bacteria. Unfortunately, in some cases the innate immune response fails to protect the host and chronic inflammation, transplant rejection, or other disorders may occur.
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191
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Di Niro R, Mesin L, Zheng NY, Stamnaes J, Morrissey M, Lee JH, Huang M, Iversen R, du Pré MF, Qiao SW, Lundin KEA, Wilson PC, Sollid LM. High abundance of plasma cells secreting transglutaminase 2-specific IgA autoantibodies with limited somatic hypermutation in celiac disease intestinal lesions. Nat Med 2012; 18:441-5. [PMID: 22366952 PMCID: PMC4533878 DOI: 10.1038/nm.2656] [Citation(s) in RCA: 157] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2011] [Accepted: 12/30/2011] [Indexed: 12/15/2022]
Abstract
Celiac disease is an immune-mediated disorder in which mucosal autoantibodies to the enzyme transglutaminase 2 (TG2) are generated in response to the exogenous antigen gluten in individuals who express human leukocyte antigen HLA-DQ2 or HLA-DQ8 (ref. 3). We assessed in a comprehensive and nonbiased manner the IgA anti-TG2 response by expression cloning of the antibody repertoire of ex vivo-isolated intestinal antibody-secreting cells (ASCs). We found that TG2-specific plasma cells are markedly expanded within the duodenal mucosa in individuals with active celiac disease. TG2-specific antibodies were of high affinity yet showed little adaptation by somatic mutations. Unlike infection-induced peripheral blood plasmablasts, the TG2-specific ASCs had not recently proliferated and were not short-lived ex vivo. Altogether, these observations demonstrate that there is a germline repertoire with high affinity for TG2 that may favor massive generation of autoreactive B cells. TG2-specific antibodies did not block enzymatic activity and served as substrates for TG2-mediated crosslinking when expressed as IgD or IgM but not as IgA1 or IgG1. This could result in preferential recruitment of plasma cells from naive IgD- and IgM-expressing B cells, thus possibly explaining why the antibody response to TG2 bears signs of a primary immune response despite the disease chronicity.
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Affiliation(s)
- Roberto Di Niro
- Centre for Immune Regulation and Department of Immunology, University of Oslo and Oslo University Hospital, N-0027 Oslo, Norway
| | - Luka Mesin
- Centre for Immune Regulation and Department of Immunology, University of Oslo and Oslo University Hospital, N-0027 Oslo, Norway
| | - Nai-Ying Zheng
- The Gwenn Knapp Center for Lupus and Immunology Research, The University of Chicago, Chicago, Illinois, 60637 USA
| | - Jorunn Stamnaes
- Centre for Immune Regulation and Department of Immunology, University of Oslo and Oslo University Hospital, N-0027 Oslo, Norway
| | - Michael Morrissey
- The Gwenn Knapp Center for Lupus and Immunology Research, The University of Chicago, Chicago, Illinois, 60637 USA
| | - Jane-Hwei Lee
- The Gwenn Knapp Center for Lupus and Immunology Research, The University of Chicago, Chicago, Illinois, 60637 USA
| | - Min Huang
- The Gwenn Knapp Center for Lupus and Immunology Research, The University of Chicago, Chicago, Illinois, 60637 USA
| | - Rasmus Iversen
- Centre for Immune Regulation and Department of Immunology, University of Oslo and Oslo University Hospital, N-0027 Oslo, Norway
| | - M. Fleur du Pré
- Centre for Immune Regulation and Department of Immunology, University of Oslo and Oslo University Hospital, N-0027 Oslo, Norway
| | - Shuo-Wang Qiao
- Centre for Immune Regulation and Department of Immunology, University of Oslo and Oslo University Hospital, N-0027 Oslo, Norway
| | - Knut E. A. Lundin
- Centre for Immune Regulation and Department of Immunology, University of Oslo and Oslo University Hospital, N-0027 Oslo, Norway
- Department of Medicine, Oslo University Hospital, N-0027 Oslo, Norway
| | - Patrick C. Wilson
- The Gwenn Knapp Center for Lupus and Immunology Research, The University of Chicago, Chicago, Illinois, 60637 USA
- Department of Medicine/ Section of Rheumatology, and The Committee on Immunology, The University of Chicago, Chicago, Illinois, 60637 USA
| | - Ludvig M. Sollid
- Centre for Immune Regulation and Department of Immunology, University of Oslo and Oslo University Hospital, N-0027 Oslo, Norway
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192
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Blander JM, Sander LE. Beyond pattern recognition: five immune checkpoints for scaling the microbial threat. Nat Rev Immunol 2012; 12:215-25. [PMID: 22362354 DOI: 10.1038/nri3167] [Citation(s) in RCA: 201] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Pattern recognition by the innate immune system enables the detection of microorganisms, but how the level of microbial threat is evaluated - a process that is crucial for eliciting measured antimicrobial responses with minimal inflammatory tissue damage - is less well understood. New evidence has shown that features of microbial viability can be detected by the immune system and thereby induce robust responses that are not warranted for dead microorganisms. Here, we propose five immune checkpoints that, as defined here, collectively determine the gravity of microbial encounters.
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Affiliation(s)
- J Magarian Blander
- Mount Sinai School of Medicine, Immunology Institute, Department of Medicine, 1425 Madison Avenue, New York, New York 10029, USA.
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193
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Cerutti A, Cols M, Gentile M, Cassis L, Barra CM, He B, Puga I, Chen K. Regulation of mucosal IgA responses: lessons from primary immunodeficiencies. Ann N Y Acad Sci 2012; 1238:132-44. [PMID: 22129060 DOI: 10.1111/j.1749-6632.2011.06266.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Adaptive co-evolution of mammals and bacteria has led to the establishment of complex commensal communities on mucosal surfaces. In spite of having available a wealth of immune-sensing and effector mechanisms capable of triggering inflammation in response to microbial intrusion, mucosal immune cells establish an intimate dialogue with microbes to generate a state of hyporesponsiveness against commensals and active readiness against pathogens. A key component of this homeostatic balance is IgA, a noninflammatory antibody isotype produced by mucosal B cells through class switching. This process involves activation of B cells by IgA-inducing signals originating from mucosal T cells, dendritic cells, and epithelial cells. Here, we review the mechanisms by which mucosal B cells undergo IgA diversification and production and discuss how the study of primary immunodeficiencies facilitates better understanding of mucosal IgA responses in humans.
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Affiliation(s)
- Andrea Cerutti
- Municipal Institute for Medical Research-Hospital del Mar, Barcelona, Spain.
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194
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Lindner C, Wahl B, Föhse L, Suerbaum S, Macpherson AJ, Prinz I, Pabst O. Age, microbiota, and T cells shape diverse individual IgA repertoires in the intestine. ACTA ACUST UNITED AC 2012; 209:365-77. [PMID: 22249449 PMCID: PMC3280880 DOI: 10.1084/jem.20111980] [Citation(s) in RCA: 179] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Intestinal immunoglobulin A (IgA) ensures host defense and symbiosis with our commensal microbiota. Yet previous studies hint at a surprisingly low diversity of intestinal IgA, and it is unknown to what extent the diverse Ig arsenal generated by somatic recombination and diversification is actually used. In this study, we analyze more than one million mouse IgA sequences to describe the shaping of the intestinal IgA repertoire, its determinants, and stability over time. We show that expanded and infrequent clones combine to form highly diverse polyclonal IgA repertoires with very little overlap between individual mice. Selective homing allows expanded clones to evenly seed the small but not large intestine. Repertoire diversity increases during aging in a dual process. On the one hand, microbiota-, T cell-, and transcription factor RORγt-dependent but Peyer's patch-independent somatic mutations drive the diversification of expanded clones, and on the other hand, new clones are introduced into the repertoire of aged mice. An individual's IgA repertoire is stable and recalled after plasma cell depletion, which is indicative of functional memory. These data provide a conceptual framework to understand the dynamic changes in the IgA repertoires to match environmental and intrinsic stimuli.
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Affiliation(s)
- Cornelia Lindner
- Institute of Immunology, Hannover Medical School, 30625 Hannover, Germany
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195
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196
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Geuking MB, McCoy KD, Macpherson AJ. The function of secretory IgA in the context of the intestinal continuum of adaptive immune responses in host-microbial mutualism. Semin Immunol 2011; 24:36-42. [PMID: 22138187 DOI: 10.1016/j.smim.2011.11.005] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The large production of immunoglobulin (Ig)A is energetically costly. The fact that evolution retained this apparent luxury of intestinal class switch recombination to IgA within the human population strongly indicates that there must be a critical specific function of IgA for survival of the species. The function of IgA has been investigated in a series of different models that will be discussed here. While IgA has clear protective functions against toxins or in the context of intestinal viral infections, the function of IgA specific for non-pathogenic commensal bacteria remains unclear. In the context of the current literature we present a hypothesis where secretory IgA integrates as an additional layer of immune function into the continuum of intestinal CD4 T cell responses, to achieve a mutualistic relationship between the intestinal commensal microbiota and the host.
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Affiliation(s)
- M B Geuking
- Maurice Müller Laboratories, DKF, Universitätsklinik für Viszerale Chirurgie und Medizin, University Hospital (Inselspital), Murtenstrasse 35, University of Bern, 3010 Bern, Switzerland
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197
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Abstract
PURPOSE OF REVIEW The review summarizes the recent progress that has been made in understanding the function of immunoglobulin A (IgA) in promoting a healthy mutualism with the commensal microbiota and protecting against pathogens. Although IgA is by far the most abundant antibody produced by mammals, direct experimental evidence for its function is still lacking. RECENT FINDINGS IgA is the predominant antibody induced in response to intestinal colonization with commensal bacteria: even fish have been shown to have a mucosal immunoglobulin (IgT), which is produced in the mucosa and coats commensals in the intestinal lumen. Recent studies indicate that intestinal IgA can be highly specific to the inducing commensals. Priming of IgA also appears to be a long-lasting response dependent on the overall dose (integral) of the bacteria sampled rather than exhibiting prime-boost effects normally observed with systemic immunoglobulin responses. Not only is human IgA highly mutated, but a mouse model with deficient hypermutation but intact class-switch recombination also shows that this mutation process (presumably leading to better anticommensal affinities) is important for IgA protection at the mucosal surface. It has been shown that some IgA can be induced independently of T cells through stimulation by epithelial cell and plasmacytoid dendritic cell cytokines including BAFF and APRIL, although the relative roles of the T-dependent and T-independent IgA pathways in generating mucosal protection are still unclear. SUMMARY Protection at mucosal surfaces through the secretion of antibodies is a phylogenetically ancient function. Mammals can produce high and low-affinity IgA against their commensal microbes via T-cell-dependent and T-cell-independent pathways to contribute to host microbial mutualism. The process of improving IgA affinity to intestinal luminal contents through somatic hypermutation of immunoglobulin genes improves the level of protection at the mucosal surface and such mutations are abundant in human IgA sequences.
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