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Shu X, Wang J, Zeng H, Shao L. Progression of Notch signaling regulation of B cells under radiation exposure. Front Immunol 2024; 15:1339977. [PMID: 38524139 PMCID: PMC10957566 DOI: 10.3389/fimmu.2024.1339977] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Accepted: 02/14/2024] [Indexed: 03/26/2024] Open
Abstract
With the continuous development of nuclear technology, the radiation exposure caused by radiation therapy is a serious health hazard. It is of great significance to further develop effective radiation countermeasures. B cells easily succumb to irradiation exposure along with immunosuppressive response. The approach to ameliorate radiation-induced B cell damage is rarely studied, implying that the underlying mechanisms of B cell damage after exposure are eager to be revealed. Recent studies suggest that Notch signaling plays an important role in B cell-mediated immune response. Notch signaling is a critical regulator for B cells to maintain immune function. Although accumulating studies reported that Notch signaling contributes to the functionality of hematopoietic stem cells and T cells, its role in B cells is scarcely appreciated. Presently, we discussed the regulation of Notch signaling on B cells under radiation exposure to provide a scientific basis to prevent radiation-induced B cell damage.
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Affiliation(s)
- Xin Shu
- Department of Occupational Health and Toxicology, School of Public Health, Jiangxi Medical College, Nanchang University, Nanchang, China
- Jiangxi Provincial Key Laboratory of Preventive Medicine, Jiangxi Medical College, School of Public Health, Nanchang University, Nanchang, China
| | - Jie Wang
- Department of Histology and Embryology, School of Basic Medicine Sciences, Nanchang University, Nanchang, China
| | - Huihong Zeng
- Department of Histology and Embryology, School of Basic Medicine Sciences, Nanchang University, Nanchang, China
| | - Lijian Shao
- Department of Occupational Health and Toxicology, School of Public Health, Jiangxi Medical College, Nanchang University, Nanchang, China
- Jiangxi Provincial Key Laboratory of Preventive Medicine, Jiangxi Medical College, School of Public Health, Nanchang University, Nanchang, China
- Jiangxi Provincial Key Laboratory of Interdisciplinary Science, Nanchang University, Nanchang, China
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Guldenpfennig C, Teixeiro E, Daniels M. NF-kB's contribution to B cell fate decisions. Front Immunol 2023; 14:1214095. [PMID: 37533858 PMCID: PMC10391175 DOI: 10.3389/fimmu.2023.1214095] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Accepted: 07/03/2023] [Indexed: 08/04/2023] Open
Abstract
NF-κB signaling is essential to an effective innate and adaptive immune response. Many immune-specific functional and developmental outcomes depend in large on NF-κB. The formidable task of sorting out the mechanisms behind the regulation and outcome of NF-κB signaling remains an important area of immunology research. Here we briefly discuss the role of NF-κB in regulating cell fate decisions at various times in the path of B cell development, activation, and the generation of long-term humoral immunity.
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Affiliation(s)
- Caitlyn Guldenpfennig
- Molecular Microbiology and Immunology, University of Missouri, Columbia, MO, United States
- NextGen Precision Health, University of Missouri, Columbia, MO, United States
| | - Emma Teixeiro
- Molecular Microbiology and Immunology, University of Missouri, Columbia, MO, United States
- NextGen Precision Health, University of Missouri, Columbia, MO, United States
| | - Mark Daniels
- Molecular Microbiology and Immunology, University of Missouri, Columbia, MO, United States
- NextGen Precision Health, University of Missouri, Columbia, MO, United States
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Riese J, Hähnel C, Menz J, Hannemann M, Khabipov A, Lührs F, Schulze T. S1PR 4 deficiency results in reduced germinal center formation but only marginally affects antibody production. Front Immunol 2022; 13:1053490. [PMID: 36532028 PMCID: PMC9755867 DOI: 10.3389/fimmu.2022.1053490] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2022] [Accepted: 11/14/2022] [Indexed: 12/03/2022] Open
Abstract
Introduction Splenic B cells exhibit a high expression of the G protein-coupled sphingosine-1-phosphate (S1P) receptor type 4 (S1PR4). Little is known about the functional relevance of S1PR4 expression on those cells. Methods In this study, S1PR4-deficient mice were used to study the role of S1PR4-mediated S1P signaling in B cell motility in vitro and for the maintenance of the splenic architecture under steady state conditions as well as in polymicrobial abdominal sepsis in vivo. Finally, the impact of S1PR4 deficiency on antibody production after immunization with T cell dependent antigens was assessed. Results Loss of S1PR4 resulted in minor alterations of the splenic architecture concerning the presence of B cell follicles. After sepsis induction, the germinal center response was severely impaired in S1PR4-deficient animals. Splenic B cells showed reduced motility in the absence of S1PR4. However, titres of specific antibodies showed only minor reductions in S1PR4-deficient animals. Discussion These observations suggest that S1P signaling mediated by S1PR4 modifies chemokine-induced splenic B cell chemotaxis, thus modulating splenic microarchitecture, GC formation and T-cell dependent antibody production.
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Affiliation(s)
| | | | | | | | | | | | - Tobias Schulze
- Experimental Surgical Research Laboratory, Department of General Surgery, Visceral, Thoracic and Vascular Surgery, Universitätsmedizin Greifswald, Greifswald, Germany
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Cencioni MT, Ali R, Nicholas R, Muraro PA. Defective CD19+CD24hiCD38hi transitional B-cell function in patients with relapsing-remitting MS. Mult Scler 2020; 27:1187-1197. [DOI: 10.1177/1352458520951536] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Background: Multiple sclerosis (MS) is characterized by central nervous system (CNS) infiltration of T and B cells, excess inflammatory cytokine and chemokine production and failure of immune regulation. CD19+CD24hiCD38hi transitional B cells producing interleukin (IL)-10 have been shown to suppress interferon-γ (IFNγ) and tumour necrosis factor-α (TNFα) production by CD4+ T cells and to be dysfunctional in autoimmune arthritis and systemic lupus erythematosus. Objective: We hypothesized that transitional B-cell-dependent immune regulation could be defective in MS and examined their function in healthy subjects and patients with relapsing-remitting multiple sclerosis (RRMS). Methods: A total of 62 healthy donors and 21 RRMS subjects donated peripheral blood for the study. IL-10-producing B cells, IFNγ and TNFα-producing T cells and proliferating T cells were quantified by flow cytometry. Results: In healthy individuals, CD19+CD24hiCD38hi transitional B cells produce more IL-10 than CD19+CD24+CD38+ naive and CD19+CD24hiCD38− memory B cells and are able to suppress CD4+ T-cell proliferation and IFNγ and TNFα-production. In subjects with RRMS, CD19+CD24hiCD38hi transitional B cells produce significantly less IL-10 and to fail to suppress effector T-cell function. Conclusion: CD19+CD24hiCD38hi transitional B cells physiologically represent the most potent regulatory B-cell subset and are functionally defective in patients with RRMS, an abnormality that may contribute to the immune pathological process.
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Affiliation(s)
- Maria T Cencioni
- Department of Brain Sciences, Imperial College London, London, UK
| | - Rehiana Ali
- Department of Brain Sciences, Imperial College London, London, UK
| | - Richard Nicholas
- Department of Brain Sciences, Imperial College London, London, UK/Imperial College Healthcare NHS Trust, London, UK
| | - Paolo A Muraro
- Wolfson Neuroscience Laboratory, Department of Brain Sciences, Imperial College London, London, UK
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Zhou Y, Zhang Y, Han J, Yang M, Zhu J, Jin T. Transitional B cells involved in autoimmunity and their impact on neuroimmunological diseases. J Transl Med 2020; 18:131. [PMID: 32183811 PMCID: PMC7079408 DOI: 10.1186/s12967-020-02289-w] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Accepted: 02/28/2020] [Indexed: 02/08/2023] Open
Abstract
Transitional B cells (TrB cells) represent a crucial link between immature B cells in the bone marrow and mature peripheral B cells. Although TrB cells represent one of the regulatory B cell subpopulations in healthy individuals, the frequency of CD24hiCD38hi TrB cells in circulation may be altered in individuals with autoimmune diseases, such as multiple sclerosis, neuromyelitisoptica spectrum disorders, systemic lupus erythematosus, Sjögren’s syndrome, rheumatoid arthritis, systemic sclerosis, and juvenile dermatomyositis. Although TrB cells play regulatory roles under inflammatory conditions, consequences of their functional impairment vary across autoimmune diseases. Since the origin, development, and function of TrB cells, especially in humans, remain unclear and controversial, this review aimed to discuss the characteristics of TrB cells at steady state and explore their role in various immune diseases, including autoimmune rheumatic diseases and neuroimmunological diseases.
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Affiliation(s)
- Yang Zhou
- Department of Neurology and Neuroscience Center, The First Hospital of Jilin University, Xinmin Street 71#, Changchun, 130021, China
| | - Ying Zhang
- Department of Neurology and Neuroscience Center, The First Hospital of Jilin University, Xinmin Street 71#, Changchun, 130021, China
| | - Jinming Han
- Department of Neurology and Neuroscience Center, The First Hospital of Jilin University, Xinmin Street 71#, Changchun, 130021, China
| | - Mengge Yang
- Department of Neurology and Neuroscience Center, The First Hospital of Jilin University, Xinmin Street 71#, Changchun, 130021, China
| | - Jie Zhu
- Department of Neurology and Neuroscience Center, The First Hospital of Jilin University, Xinmin Street 71#, Changchun, 130021, China.,Department of Neurobiology, Care Sciences and Society, Karolinska Institute, Stockholm, Sweden
| | - Tao Jin
- Department of Neurology and Neuroscience Center, The First Hospital of Jilin University, Xinmin Street 71#, Changchun, 130021, China.
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Ghirotto B, Terra FF, Câmara NOS, Basso PJ. Sirtuins in B lymphocytes metabolism and function. World J Exp Med 2019; 9:1-13. [PMID: 30705866 PMCID: PMC6354076 DOI: 10.5493/wjem.v9.i1.1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Revised: 10/29/2018] [Accepted: 01/05/2019] [Indexed: 02/06/2023] Open
Abstract
Sirtuins (SIRTs) are NAD+-dependent histone deacetylases and play a role in virtually all cell biological processes. As SIRTs functions vary according to their subtypes, they can either activate or inhibit signaling pathways upon different conditions or tissues. Recent studies have focused on metabolic effects performed by SIRTs in several cell types since specific metabolic pathways (e.g., aerobic glycolysis, oxidative phosphorylation, β-oxidation, glutaminolysis) are used to determine the cell fate. However, few efforts have been made to understand the role of SIRTs on B lymphocytes metabolism and function. These cells are associated with humoral immune responses by secreting larger amounts of antibodies after differentiating into antibody-secreting cells. Besides, both the SIRTs and B lymphocytes are potential targets to treat several immune-mediated disorders, including cancer. Here, we provide an outlook of recent studies regarding the role of SIRTs in general cellular metabolism and B lymphocytes functions, pointing out the future perspectives of this field.
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Affiliation(s)
- Bruno Ghirotto
- Department of Immunology, Institute of Biomedical Sciences, University of São Paulo, São Paulo 05508-000, Brazil
| | - Fernanda Fernandes Terra
- Department of Immunology, Institute of Biomedical Sciences, University of São Paulo, São Paulo 05508-000, Brazil
| | - Niels Olsen Saraiva Câmara
- Department of Immunology, Institute of Biomedical Sciences, University of São Paulo, São Paulo 05508-000, Brazil
- Division of Nephrology, School of Medicine, Federal University of São Paulo, São Paulo 04023-062, Brazil
- Laboratory of Renal Physiology (LIM 16), School of Medicine, University of São Paulo, São Paulo 01246-903, Brazil
| | - Paulo José Basso
- Department of Immunology, Institute of Biomedical Sciences, University of São Paulo, São Paulo 05508-000, Brazil
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Pipi E, Nayar S, Gardner DH, Colafrancesco S, Smith C, Barone F. Tertiary Lymphoid Structures: Autoimmunity Goes Local. Front Immunol 2018; 9:1952. [PMID: 30258435 PMCID: PMC6143705 DOI: 10.3389/fimmu.2018.01952] [Citation(s) in RCA: 107] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2018] [Accepted: 08/07/2018] [Indexed: 12/18/2022] Open
Abstract
Tertiary lymphoid structures (TLS) are frequently observed in target organs of autoimmune diseases. TLS present features of secondary lymphoid organs such as segregated T and B cell zones, presence of follicular dendritic cell networks, high endothelial venules and specialized lymphoid fibroblasts and display the mechanisms to support local adaptive immune responses toward locally displayed antigens. TLS detection in the tissue is often associated with poor prognosis of disease, auto-antibody production and malignancy development. This review focuses on the contribution of TLS toward the persistence of the inflammatory drive, the survival of autoreactive lymphocyte clones and post-translational modifications, responsible for the pathogenicity of locally formed autoantibodies, during autoimmune disease development.
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Affiliation(s)
- Elena Pipi
- Rheumatology Research Group, Institute of Inflammation and Ageing, University of Birmingham, Birmingham, United Kingdom.,Experimental Medicine Unit, Immuno-Inflammation Therapeutic Area, GSK Medicines Research Centre, Stevenage, United Kingdom
| | - Saba Nayar
- Rheumatology Research Group, Institute of Inflammation and Ageing, University of Birmingham, Birmingham, United Kingdom
| | - David H Gardner
- Rheumatology Research Group, Institute of Inflammation and Ageing, University of Birmingham, Birmingham, United Kingdom
| | | | - Charlotte Smith
- Rheumatology Research Group, Institute of Inflammation and Ageing, University of Birmingham, Birmingham, United Kingdom
| | - Francesca Barone
- Rheumatology Research Group, Institute of Inflammation and Ageing, University of Birmingham, Birmingham, United Kingdom
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Ye ZW, Yuan S, Poon KM, Wen L, Yang D, Sun Z, Li C, Hu M, Shuai H, Zhou J, Zhang MY, Zheng BJ, Chu H, Yuen KY. Antibody-Dependent Cell-Mediated Cytotoxicity Epitopes on the Hemagglutinin Head Region of Pandemic H1N1 Influenza Virus Play Detrimental Roles in H1N1-Infected Mice. Front Immunol 2017; 8:317. [PMID: 28377769 PMCID: PMC5359280 DOI: 10.3389/fimmu.2017.00317] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2017] [Accepted: 03/06/2017] [Indexed: 01/07/2023] Open
Abstract
Engaging the antibody-dependent cell-mediated cytotoxicity (ADCC) for killing of virus-infected cells and secretion of antiviral cytokines and chemokines was incorporated as one of the important features in the design of universal influenza vaccines. However, investigation of the ADCC epitopes on the highly immunogenic influenza hemagglutinin (HA) head region has been rarely reported. In this study, we determined the ADCC and antiviral activities of two putative ADCC epitopes, designated E1 and E2, on the HA head of a pandemic H1N1 influenza virus in vitro and in a lethal mouse model. Our data demonstrated that sera from the E1-vaccinated mice could induce high ADCC activities. Importantly, the induction of ADCC response modestly decreased viral load in the lungs of H1N1-infected mice. However, the elevated ADCC significantly increased mouse alveolar damage and mortality than that of the PBS-vaccinated group (P < 0.0001). The phenotype was potentially due to an exaggerated inflammatory cell infiltration triggered by ADCC, as an upregulated release of cytotoxic granules (perforin) was observed in the lung tissue of E1-vaccinated mice after H1N1 influenza virus challenge. Overall, our data suggested that ADCC elicited by certain domains of HA head region might have a detrimental rather than protective effect during influenza virus infection. Thus, future design of universal influenza vaccine shall strike a balance between the induction of protective immunity and potential side effects of ADCC.
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Affiliation(s)
- Zi-Wei Ye
- Department of Microbiology, The University of Hong Kong , Hong Kong
| | - Shuofeng Yuan
- Department of Microbiology, The University of Hong Kong , Hong Kong
| | - Kwok-Man Poon
- Department of Microbiology, The University of Hong Kong , Hong Kong
| | - Lei Wen
- Department of Microbiology, The University of Hong Kong , Hong Kong
| | - Dong Yang
- Department of Microbiology, The University of Hong Kong , Hong Kong
| | - Zehua Sun
- Department of Microbiology, The University of Hong Kong , Hong Kong
| | - Cun Li
- Department of Microbiology, The University of Hong Kong , Hong Kong
| | - Meng Hu
- Department of Microbiology, The University of Hong Kong , Hong Kong
| | - Huiping Shuai
- Department of Microbiology, The University of Hong Kong , Hong Kong
| | - Jie Zhou
- Department of Microbiology, The University of Hong Kong, Hong Kong; State Key Laboratory of Emerging Infectious Diseases, The University of Hong Kong, Hong Kong
| | - Mei-Yun Zhang
- Department of Microbiology, The University of Hong Kong , Hong Kong
| | - Bo-Jian Zheng
- Department of Microbiology, The University of Hong Kong , Hong Kong
| | - Hin Chu
- Department of Microbiology, The University of Hong Kong, Hong Kong; State Key Laboratory of Emerging Infectious Diseases, The University of Hong Kong, Hong Kong
| | - Kwok-Yung Yuen
- Department of Microbiology, The University of Hong Kong, Hong Kong; State Key Laboratory of Emerging Infectious Diseases, The University of Hong Kong, Hong Kong; Research Centre of Infection and Immunology, The University of Hong Kong, Hong Kong; Carol Yu Centre for Infection, The University of Hong Kong, Hong Kong
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Benitez A, Weldon AJ, Tatosyan L, Velkuru V, Lee S, Milford TA, Francis OL, Hsu S, Nazeri K, Casiano CM, Schneider R, Gonzalez J, Su RJ, Baez I, Colburn K, Moldovan I, Payne KJ. Differences in mouse and human nonmemory B cell pools. THE JOURNAL OF IMMUNOLOGY 2014; 192:4610-9. [PMID: 24719464 DOI: 10.4049/jimmunol.1300692] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Identifying cross-species similarities and differences in immune development and function is critical for maximizing the translational potential of animal models. Coexpression of CD21 and CD24 distinguishes transitional and mature B cell subsets in mice. In this study, we validate these markers for identifying analogous subsets in humans and use them to compare the nonmemory B cell pools in mice and humans, across tissues, and during fetal/neonatal and adult life. Among human CD19(+)IgM(+) B cells, the CD21/CD24 schema identifies distinct populations that correspond to transitional 1 (T1), transitional 2 (T2), follicular mature, and marginal zone subsets identified in mice. Markers specific to human B cell development validate the identity of marginal zone cells and the maturation status of human CD21/CD24 nonmemory B cell subsets. A comparison of the nonmemory B cell pools in bone marrow, blood, and spleen in mice and humans shows that transitional B cells comprise a much smaller fraction in adult humans than mice. T1 cells are a major contributor to the nonmemory B cell pool in mouse bone marrow, in which their frequency is more than twice that in humans. Conversely, in spleen, the T1:T2 ratio shows that T2 cells are proportionally ∼ 8-fold higher in humans than in mice. Despite the relatively small contribution of transitional B cells to the human nonmemory pool, the number of naive follicular mature cells produced per transitional B cell is 3- to 6-fold higher across tissues than in mice. These data suggest differing dynamics or mechanisms produce the nonmemory B cell compartments in mice and humans.
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Affiliation(s)
- Abigail Benitez
- Department of Basic Sciences, Loma Linda University, Loma Linda, CA 92350
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Agrawal S, Smith SABC, Tangye SG, Sewell WA. Transitional B cell subsets in human bone marrow. Clin Exp Immunol 2013; 174:53-9. [PMID: 23731328 DOI: 10.1111/cei.12149] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/28/2013] [Indexed: 01/05/2023] Open
Abstract
B cells originate from precursors in the bone marrow, and the first cells which migrate to the peripheral blood have been classified as 'transitional B cells'. Transitional B cells have been characterized in human blood with stage 1 (T1) and stage 2 (T2) subsets being proposed. In the present study, 27 normal human bone marrow samples were analysed for transitional B cell markers by eight-colour flow cytometry. T1 transitional B cells (CD45(+)CD19(+)CD10(+)IgM(+)IgD(lo)) and T2 transitional B cells (CD45(+)CD19(+)CD10(+)IgM(+)IgD(+)) were identified in normal bone marrow samples at a mean frequency of 3·2 and 3·1% of total B lineage cells, respectively. A majority of the bone marrow transitional B cells were CD24(hi)CD38(hi) , the phenotype of blood transitional B cells. Consistent with recent peripheral blood data, T2 B cells had a significantly higher CD21 expression compared with T1 B cells (72·4 versus 40·9%) in the bone marrow. These data raise the possibility that transitional B cells are capable of differentiating from T1 to T2 B cells within the bone marrow. Furthermore, transitional cells at either stages 1 or 2 might be capable of migrating out of the bone marrow.
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Affiliation(s)
- S Agrawal
- Immunology Department, SydPath, St Vincent's Pathology, St Vincent's Hospital Sydney, NSW, Australia; St Vincent's Clinical School, University of NSW, NSW, Australia; Garvan Institute of Medical Research, Darlinghurst, NSW, Australia
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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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