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Bottero M, Pessina G, Bason C, Vigo T, Uccelli A, Ferrara G. Nerve-Glial antigen 2: unmasking the enigmatic cellular identity in the central nervous system. Front Immunol 2024; 15:1393842. [PMID: 39136008 PMCID: PMC11317297 DOI: 10.3389/fimmu.2024.1393842] [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: 02/29/2024] [Accepted: 07/05/2024] [Indexed: 08/15/2024] Open
Abstract
Chondroitin sulfate proteoglycans (CSPGs) are fundamental components of the extracellular matrix in the central nervous system (CNS). Among these, the Nerve-Glial antigen 2 (NG2) stands out as a transmembrane CSPG exclusively expressed in a different population of cells collectively termed NG2-expressing cells. These enigmatic cells, found throughout the developing and adult CNS, have been indicated with various names, including NG2 progenitor cells, polydendrocytes, synantocytes, NG2 cells, and NG2-Glia, but are more commonly referred to as oligodendrocyte progenitor cells. Characterized by high proliferation rates and unique morphology, NG2-expressing cells stand apart from neurons, astrocytes, and oligodendrocytes. Intriguingly, some NG2-expressing cells form functional glutamatergic synapses with neurons, challenging the long-held belief that only neurons possess the intricate machinery required for neurotransmission. In the CNS, the complexity surrounding NG2-expressing cells extends to their classification. Additionally, NG2 expression has been documented in pericytes and immune cells, suggesting a role in regulating brain innate immunity and neuro-immune crosstalk in homeostasis. Ongoing debates revolve around their heterogeneity, potential as progenitors for various cell types, responses to neuroinflammation, and the role of NG2. Therefore, this review aims to shed light on the enigma of NG2-expressing cells by delving into their structure, functions, and signaling pathways. We will critically evaluate the literature on NG2 expression across the CNS, and address the contentious issues surrounding their classification and roles in neuroinflammation and neurodegeneration. By unraveling the intricacies of NG2-expressing cells, we hope to pave the way for a more comprehensive understanding of their contributions to CNS health and during neurological disorders.
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Affiliation(s)
- Marta Bottero
- IRCCS Ospedale Policlinico San Martino, Genoa, Italy
| | - Giada Pessina
- Department of Experimental Medicine, University of Genoa, Genoa, Italy
| | | | - Tiziana Vigo
- IRCCS Ospedale Policlinico San Martino, Genoa, Italy
| | - Antonio Uccelli
- IRCCS Ospedale Policlinico San Martino, Genoa, Italy
- Department of Neurology, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, Genoa, Italy
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2
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Maslanka J, Torres G, Londregan J, Goldman N, Silberman D, Somerville J, Riggs JE. Loss of B1 and marginal zone B cells during ovarian cancer. Cell Immunol 2024; 395-396:104788. [PMID: 38000306 PMCID: PMC10842900 DOI: 10.1016/j.cellimm.2023.104788] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Revised: 10/31/2023] [Accepted: 11/20/2023] [Indexed: 11/26/2023]
Abstract
Recent advances in immunotherapy have not addressed the challenge presented by ovarian cancer. Although the peritoneum is an "accessible" locus for this disease there has been limited characterization of the immunobiology therein. We investigated the ID8-C57BL/6J ovarian cancer model and found marked depletion of B1 cells from the ascites of the peritoneal cavity. There was also selective loss of the B1 and marginal zone B cell subsets from the spleen. Immunity to antigens that activate these subsets validated their loss rather than relocation. A marked influx of myeloid-derived suppressor cells correlated with B cell subset depletion. These observations are discussed in the context of the housekeeping burden placed on innate B cells during ovarian cancer and to foster consideration of B cell biology in therapeutic strategies to address this challenge.
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Affiliation(s)
- Jeffrey Maslanka
- Department of Biology, Rider University, Lawrenceville, NJ 08648, USA
| | - Gretel Torres
- Department of Biology, Rider University, Lawrenceville, NJ 08648, USA
| | | | - Naomi Goldman
- Department of Biology, Rider University, Lawrenceville, NJ 08648, USA
| | - Daniel Silberman
- Department of Biology, Rider University, Lawrenceville, NJ 08648, USA
| | - John Somerville
- Department of Biology, Rider University, Lawrenceville, NJ 08648, USA
| | - James E Riggs
- Department of Biology, Rider University, Lawrenceville, NJ 08648, USA.
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3
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Yiu YY, Hansen PS, Torrez Dulgeroff LB, Blacker G, Myers L, Galloway S, Gars E, Colace O, Mansfield P, Hasenkrug KJ, Weissman IL, Tal MC. CD47 Blockade Leads to Chemokine-Dependent Monocyte Infiltration and Loss of B Cells from the Splenic Marginal Zone. THE JOURNAL OF IMMUNOLOGY 2022; 208:1371-1377. [PMID: 35236754 PMCID: PMC9012117 DOI: 10.4049/jimmunol.2100352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Accepted: 01/11/2022] [Indexed: 11/19/2022]
Abstract
CD47 is an important innate immune checkpoint through its interaction with its inhibitory receptor on macrophages, signal-regulatory protein α (SIRPα). Therapeutic blockade of CD47-SIRPα interactions is a promising immuno-oncology treatment that promotes clearance of cancer cells. However, CD47-SIRPα interactions also maintain homeostatic lymphocyte levels. In this study, we report that the mouse splenic marginal zone B cell population is dependent on intact CD47-SIRPα interactions and blockade of CD47 leads to the loss of these cells. This depletion is accompanied by elevated levels of monocyte-recruiting chemokines CCL2 and CCL7 and infiltration of CCR2+Ly6Chi monocytes into the mouse spleen. In the absence of CCR2 signaling, there is no infiltration and reduced marginal zone B cell depletion. These data suggest that CD47 blockade leads to clearance of splenic marginal zone B cells.
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Affiliation(s)
- Ying Ying Yiu
- Institute for Stem Cell Biology and Regenerative Medicine and the Ludwig Cancer Center, Stanford University School of Medicine, Stanford, CA
- Immunology Program, Stanford University, Stanford, CA
| | - Paige S Hansen
- Institute for Stem Cell Biology and Regenerative Medicine and the Ludwig Cancer Center, Stanford University School of Medicine, Stanford, CA
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA
| | - Laughing Bear Torrez Dulgeroff
- Institute for Stem Cell Biology and Regenerative Medicine and the Ludwig Cancer Center, Stanford University School of Medicine, Stanford, CA
| | - Grace Blacker
- Institute for Stem Cell Biology and Regenerative Medicine and the Ludwig Cancer Center, Stanford University School of Medicine, Stanford, CA
| | - Lara Myers
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT
| | - Sarah Galloway
- Institute for Stem Cell Biology and Regenerative Medicine and the Ludwig Cancer Center, Stanford University School of Medicine, Stanford, CA
| | - Eric Gars
- Department of Pathology, Stanford University School of Medicine, Stanford, CA
| | - Olivia Colace
- Institute for Stem Cell Biology and Regenerative Medicine and the Ludwig Cancer Center, Stanford University School of Medicine, Stanford, CA
| | - Paul Mansfield
- Institute for Stem Cell Biology and Regenerative Medicine and the Ludwig Cancer Center, Stanford University School of Medicine, Stanford, CA
| | - Kim J Hasenkrug
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT
| | - Irving L Weissman
- Institute for Stem Cell Biology and Regenerative Medicine and the Ludwig Cancer Center, Stanford University School of Medicine, Stanford, CA;
- Department of Pathology, Stanford University School of Medicine, Stanford, CA
- Ludwig Center for Cancer Stem Cell Research and Medicine, Stanford University School of Medicine, Stanford, CA; and
- Stanford Cancer Institute, Stanford University School of Medicine, Stanford, CA
| | - Michal Caspi Tal
- Institute for Stem Cell Biology and Regenerative Medicine and the Ludwig Cancer Center, Stanford University School of Medicine, Stanford, CA;
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA
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Yang M, Yi P, Jiang J, Zhao M, Wu H, Lu Q. Dysregulated translational factors and epigenetic regulations orchestrate in B cells contributing to autoimmune diseases. Int Rev Immunol 2021; 42:1-25. [PMID: 34445929 DOI: 10.1080/08830185.2021.1964498] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
B cells play a crucial role in antigen presentation, antibody production and pro-/anti-inflammatory cytokine secretion in adaptive immunity. Several translational factors including transcription factors and cytokines participate in the regulation of B cell development, with the cooperation of epigenetic regulations. Autoimmune diseases are generally characterized with autoreactive B cells and high-level pathogenic autoantibodies. The success of B cell depletion therapy in mouse model and clinical trials has proven the role of B cells in pathogenesis of autoimmune diseases. The failure of B cell tolerance in immune checkpoints results in accumulated autoreactive naïve B (BN) cells with aberrant B cell receptor signaling and dysregulated B cell response, contributing to self-antibody-mediated autoimmune reaction. Dysregulation of translational factors and epigenetic alterations in B cells has been demonstrated to correlate with aberrant B cell compartment in autoimmune diseases, such as systemic lupus erythematosus, rheumatoid arthritis, primary Sjögren's syndrome, multiple sclerosis, diabetes mellitus and pemphigus. This review is intended to summarize the interaction of translational factors and epigenetic regulations that are involved with development and differentiation of B cells, and the mechanism of dysregulation in the pathogenesis of autoimmune diseases.
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Affiliation(s)
- Ming Yang
- Department of Dermatology, Second Xiangya Hospital, Central South University, Hunan Key Laboratory of Medical Epigenomics, Changsha, Hunan, China
| | - Ping Yi
- Department of Dermatology, Second Xiangya Hospital, Central South University, Hunan Key Laboratory of Medical Epigenomics, Changsha, Hunan, China
| | - Jiao Jiang
- Department of Dermatology, Second Xiangya Hospital, Central South University, Hunan Key Laboratory of Medical Epigenomics, Changsha, Hunan, China
| | - Ming Zhao
- Department of Dermatology, Second Xiangya Hospital, Central South University, Hunan Key Laboratory of Medical Epigenomics, Changsha, Hunan, China
| | - Haijing Wu
- Department of Dermatology, Second Xiangya Hospital, Central South University, Hunan Key Laboratory of Medical Epigenomics, Changsha, Hunan, China
| | - Qianjin Lu
- Department of Dermatology, Second Xiangya Hospital, Central South University, Hunan Key Laboratory of Medical Epigenomics, Changsha, Hunan, China.,Department of Dermatology, Institute of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College, Nanjing, Jiangsu, China
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Stranavova L, Hruba P, Slatinska J, Sawitzki B, Reinke P, Volk HD, Viklicky O. Dialysis therapy is associated with peripheral marginal zone B-cell augmentation. Transpl Immunol 2020; 60:101289. [PMID: 32229239 DOI: 10.1016/j.trim.2020.101289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Revised: 03/24/2020] [Accepted: 03/25/2020] [Indexed: 11/17/2022]
Abstract
Chronic kidney disease stage 5 (CKD5) dialysis patients who stay long term in uremic environment often exhibit several, poorly defined, immune impairments. In this study, we assessed peripheral virus-specific effector/memory cells and subpopulations of T, B and DC cells using ELISPOT and FACS methods in 74 low-risk kidney transplant candidates without anti-HLA antibodies, prior to transplantation in pre-emptive (never experienced dialysis) and dialysis cohorts. There was difference in circulating marginal zone B cells (MZB) (IgDhighCD27high) between dialysis patients and those receiving kidney grafts pre-emptively (P = .002). Patients treated on dialysis >12 months had also 4.2-fold greater risk of increased absolute numbers of MZB (95%CI:1.6-11.2; P = .004). There were no other differences in B-, T- and DC-cell subsets. Numbers of effector/memory T cells reactive to major opportunistic virus-specific antigens (CMV, BKV and EBV) were not affected by dialysis. Non-sensitised dialysis-treated patients displayed significantly more circulating MZB compared to those CKD5 patients that had never undergone dialysis therapy.
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Affiliation(s)
- Lucia Stranavova
- Transplant Laboratory, Institute for Clinical and Experimental Medicine (IKEM), Prague, Czech Republic
| | - Petra Hruba
- Transplant Laboratory, Institute for Clinical and Experimental Medicine (IKEM), Prague, Czech Republic
| | - Janka Slatinska
- Department of Nephrology, Institute for Clinical and Experimental Medicine (IKEM), Prague, Czech Republic
| | - Birgit Sawitzki
- BIH Centre for Regenerative Therapies, Berlin Centre for Advanced Therapies, Charité University Medicine Berlin, Berlin, Germany
| | - Petra Reinke
- BIH Centre for Regenerative Therapies, Berlin Centre for Advanced Therapies, Charité University Medicine Berlin, Berlin, Germany
| | - Hans-Dieter Volk
- BIH Centre for Regenerative Therapies, Berlin Centre for Advanced Therapies, Charité University Medicine Berlin, Berlin, Germany
| | - Ondrej Viklicky
- Transplant Laboratory, Institute for Clinical and Experimental Medicine (IKEM), Prague, Czech Republic; Department of Nephrology, Institute for Clinical and Experimental Medicine (IKEM), Prague, Czech Republic.
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Zhen Y, Shao WH. Experimental Analysis of Apoptotic Thymocyte Engulfment by Macrophages. J Vis Exp 2019. [PMID: 31180346 DOI: 10.3791/59731] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Cell apoptosis is a natural process and plays a critical role in embryonic development, homeostatic regulation, immune tolerance induction, and resolution of inflammation. Accumulation of apoptotic debris in the body may trigger chronic inflammatory responses that lead to systemic autoimmune diseases over time. Impaired apoptotic cell clearance has been implicated in a variety of autoimmune diseases. Apoptotic clearance is a complex process rarely detected under physiological conditions. It involves abundant surface receptors and signaling molecules. Studying the process of apoptotic cell clearance provides insightful molecular mechanisms and subsequent biological responses, which may lead to the development of new therapeutics. Here, we describe protocols for the induction of apoptotic thymocytes, the preparation of peritoneal macrophages, and the analysis of apoptotic cell clearance by flow cytometry and microscopy. All cells will undergo apoptosis at a certain stage, and many residential and circulating cells can uptake apoptotic debris. Therefore, the protocol described here can be used in many applications to characterize apoptotic cell binding and ingestion by many other cell types.
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Affiliation(s)
- Yuxuan Zhen
- Division of Immunology, Allergy, and Rheumatology, Department of Internal Medicine, College of Medicine, University of Cincinnati
| | - Wen-Hai Shao
- Division of Immunology, Allergy, and Rheumatology, Department of Internal Medicine, College of Medicine, University of Cincinnati;
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Abstract
Defective clearance of apoptotic cells in MFG-E8 deficient mice results in lupus-like disease in the mixed B6x129, but not pure B6 background. The lack of overt autoimmunity in MFG-E8-/- B6 mice suggests that accumulation of apoptotic cells is not sufficient to break central tolerance. However, the delayed clearance of apoptotic cells in the follicles of MFG-E8-/- B6 mice provides an excellent opportunity to investigate how B cells respond to excessive apoptotic cells in the periphery under relatively non-inflammatory conditions. In MFG-E8-/- B6 mice, we found increased IgG2c production against apoptotic cells and oxidized LDL. Apoptotic cell induced antibody responses depended on MyD88 signal and T cell help. In addition, MFG-E8-/- B6 mice had enlarged MZ B cell compartments as well as an enhanced antibody response to NP-Ficoll. Moreover, a significant percentage of MZ B cells in aged MFG-E8-/- B6 mice migrated into follicles. Injecting apoptotic cells or oxidized LDL into wild type mice as well as physiological accumulation of LDL in ApoE-/- mice recapitulated the translocation of MZ B cells. To determine how MFG-E8 deficiency affects the functions of autoreactive B cells specific for nucleic acids in the periphery under non-inflammatory conditions, we utilized BCR transgenic mice to bypass central selection and compared the differentiation of TLR9 dependent anti-dsDNA 56R B cells and TLR7 dependent anti-ssRNA H564 B cells in MFG-E8-/- mice. In MFG-E8-/- 56R mice, anti-dsDNA specific 56R/Vκ38c B cells differentiated into MZ B cells but not AFCs. On the contrary, in MFG-E8-/-H564 mice, anti-ssRNA specific H564 B cells further differentiated into GC B cells and AFCs. Adoptive transfer of activated autoreactive B cells confirmed that H564 B cells were more sensitive to apoptotic cell antigens than 56R B cells. Our observations provide new insights about the MZ B cell translocation in lupus patients as well as the dichotomy of TLR9 and TLR7 signals in the pathogenesis of lupus.
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Affiliation(s)
- YuFeng Peng
- Division of Rheumatology, Department of Medicine, University of Washington, Seattle, Washington, United States of America
- * E-mail:
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8
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Abstract
The importance of ethnicity, socioeconomic status (SES), and autoantibodies as prognostic indicators in lupus were evaluated in a Canadian cohort. A retrospective review of 330 lupus patients identified demographic features including age and self reported ethnicity, SES, lupus features, antibodies to extractable nuclear antigens (ENAs), organ damage (SDI score), and mortality. ENA (Sm, RNP, Ro, La) associations with lupus features, predictors of final visit SDI score and the contributions of ethnicity, autoantibodies and SES on overall mortality were determined. Three ethnic groups [Caucasians (C), Asian-Orientals (AO), Native American First Nations (FN)] differed in disease severity and SES. FN and AO patients had similarly severe lupus, developing lupus at an earlier age, with more renal and neurological involvement, greater SDI scores at last visit, and more frequently had Sm or RNP antibodies than C. FN had the highest mortality and lowest SES. Sm and RNP antibodies were associated with renal and neurologic involvement. RNP, education and duration of follow-up predicted SDI score. Sm increased risk of death. In conclusion, RNP and lower SES are associated with lupus related organ damage and the presence of Sm is a predictor of mortality in lupus, independent of ethnicity, renal involvement or socioeconomic status.
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Affiliation(s)
- C A Hitchon
- Arthritis Center, University of Manitoba, Manitoba, Canada.
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9
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Ding C, Chen X, Dascani P, Hu X, Bolli R, Zhang HG, Mcleish KR, Yan J. STAT3 Signaling in B Cells Is Critical for Germinal Center Maintenance and Contributes to the Pathogenesis of Murine Models of Lupus. THE JOURNAL OF IMMUNOLOGY 2016; 196:4477-86. [PMID: 27183592 DOI: 10.4049/jimmunol.1502043] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2015] [Accepted: 03/30/2016] [Indexed: 01/18/2023]
Abstract
Ab maturation as well as memory B and plasma cell differentiation occur primarily in the germinal centers (GCs). Systemic lupus erythematosus (SLE) may develop as a result of enhanced GC activity. Previous studies have shown that the dysregulated STAT3 pathway is linked to lupus pathogenesis. However, the exact role of STAT3 in regulating SLE disease progression has not been fully understood. In this study, we demonstrated that STAT3 signaling in B cells is essential for GC formation and maintenance as well as Ab response. Increased cell apoptosis and downregulated Bcl-xL and Mcl-1 antiapoptotic gene expression were found in STAT3-deficient GC B cells. The follicular helper T cell response positively correlated with GC B cells and was significantly decreased in immunized B cell STAT3-deficient mice. STAT3 deficiency also led to the defect of plasma cell differentiation. Furthermore, STAT3 deficiency in autoreactive B cells resulted in decreased autoantibody production. Results obtained from B cell STAT3-deficient B6.MRL/lpr mice suggest that STAT3 signaling significantly contributes to SLE pathogenesis by regulation of GC reactivity, autoantibody production, and kidney pathology. Our findings provide new insights into the role of STAT3 signaling in the maintenance of GC formation and GC B cell differentiation and identify STAT3 as a novel target for treatment of SLE.
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Affiliation(s)
- Chuanlin Ding
- Department of Medicine, James Graham Brown Cancer Center, University of Louisville School of Medicine, Louisville, KY 40202;
| | - Xingguo Chen
- Department of Rheumatology, Nanjing First Hospital, Nanjing Medical University, Nanjing 210006, People's Republic of China
| | - Paul Dascani
- Department of Microbiology and Immunology, University of Louisville School of Medicine, Louisville, KY 40202
| | - Xiaoling Hu
- Department of Medicine, James Graham Brown Cancer Center, University of Louisville School of Medicine, Louisville, KY 40202
| | - Roberto Bolli
- Department of Medicine, Institute of Molecular Cardiology, University of Louisville, Louisville, KY 40292; and
| | - Huang-Ge Zhang
- Department of Microbiology and Immunology, University of Louisville School of Medicine, Louisville, KY 40202
| | - Kenneth R Mcleish
- Section of Nephrology, Department of Medicine, University of Louisville, Louisville, KY 40202
| | - Jun Yan
- Department of Medicine, James Graham Brown Cancer Center, University of Louisville School of Medicine, Louisville, KY 40202; Department of Microbiology and Immunology, University of Louisville School of Medicine, Louisville, KY 40202;
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Kang S, Rogers JL, Monteith AJ, Jiang C, Schmitz J, Clarke SH, Tarrant TK, Truong YK, Diaz M, Fedoriw Y, Vilen BJ. Apoptotic Debris Accumulates on Hematopoietic Cells and Promotes Disease in Murine and Human Systemic Lupus Erythematosus. THE JOURNAL OF IMMUNOLOGY 2016; 196:4030-9. [PMID: 27059595 DOI: 10.4049/jimmunol.1500418] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2015] [Accepted: 03/05/2016] [Indexed: 11/19/2022]
Abstract
Apoptotic debris, autoantibody, and IgG-immune complexes (ICs) have long been implicated in the inflammation associated with systemic lupus erythematosus (SLE); however, it remains unclear whether they initiate immune-mediated events that promote disease. In this study, we show that PBMCs from SLE patients experiencing active disease, and hematopoietic cells from lupus-prone MRL/lpr and NZM2410 mice accumulate markedly elevated levels of surface-bound nuclear self-antigens. On dendritic cells (DCs) and macrophages (MFs), the self-antigens are part of IgG-ICs that promote FcγRI-mediated signal transduction. Accumulation of IgG-ICs is evident on ex vivo myeloid cells from MRL/lpr mice by 10 wk of age and steadily increases prior to lupus nephritis. IgG and FcγRI play a critical role in disease pathology. Passive transfer of pathogenic IgG into IgG-deficient MRL/lpr mice promotes the accumulation of IgG-ICs prior to significant B cell expansion, BAFF secretion, and lupus nephritis. In contrast, diminishing the burden IgG-ICs in MRL/lpr mice through deficiency in FcγRI markedly improves these lupus pathologies. Taken together, our findings reveal a previously unappreciated role for the cell surface accumulation of IgG-ICs in human and murine lupus.
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Affiliation(s)
- SunAh Kang
- Department of Microbiology and Immunology, University of North Carolina, Chapel Hill, NC 27599
| | - Jennifer L Rogers
- Division of Rheumatology, Allergy, and Immunology, Thurston Arthritis Research Center, Department of Medicine, University of North Carolina, Chapel Hill, NC 27599
| | - Andrew J Monteith
- Department of Microbiology and Immunology, University of North Carolina, Chapel Hill, NC 27599; Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, NC 27599
| | - Chuancang Jiang
- Laboratory of Molecular Genetics, National Institute of Environmental Health Sciences/National Institutes of Health, Research Triangle Park, NC 27709
| | - John Schmitz
- Department of Pathology and Laboratory Medicine, University of North Carolina, Chapel Hill, NC 27599; and
| | - Stephen H Clarke
- Department of Microbiology and Immunology, University of North Carolina, Chapel Hill, NC 27599
| | - Teresa K Tarrant
- Division of Rheumatology, Allergy, and Immunology, Thurston Arthritis Research Center, Department of Medicine, University of North Carolina, Chapel Hill, NC 27599
| | - Young K Truong
- Department of Biostatistics, University of North Carolina, Chapel Hill, NC 27599
| | - Marilyn Diaz
- Laboratory of Molecular Genetics, National Institute of Environmental Health Sciences/National Institutes of Health, Research Triangle Park, NC 27709
| | - Yuri Fedoriw
- Department of Pathology and Laboratory Medicine, University of North Carolina, Chapel Hill, NC 27599; and
| | - Barbara J Vilen
- Department of Microbiology and Immunology, University of North Carolina, Chapel Hill, NC 27599;
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11
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Martin KR, Kantari-Mimoun C, Yin M, Pederzoli-Ribeil M, Angelot-Delettre F, Ceroi A, Grauffel C, Benhamou M, Reuter N, Saas P, Frachet P, Boulanger CM, Witko-Sarsat V. Proteinase 3 Is a Phosphatidylserine-binding Protein That Affects the Production and Function of Microvesicles. J Biol Chem 2016; 291:10476-89. [PMID: 26961880 DOI: 10.1074/jbc.m115.698639] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Indexed: 01/05/2023] Open
Abstract
Proteinase 3 (PR3), the autoantigen in granulomatosis with polyangiitis, is expressed at the plasma membrane of resting neutrophils, and this membrane expression increases during both activation and apoptosis. Using surface plasmon resonance and protein-lipid overlay assays, this study demonstrates that PR3 is a phosphatidylserine-binding protein and this interaction is dependent on the hydrophobic patch responsible for membrane anchorage. Molecular simulations suggest that PR3 interacts with phosphatidylserine via a small number of amino acids, which engage in long lasting interactions with the lipid heads. As phosphatidylserine is a major component of microvesicles (MVs), this study also examined the consequences of this interaction on MV production and function. PR3-expressing cells produced significantly fewer MVs during both activation and apoptosis, and this reduction was dependent on the ability of PR3 to associate with the membrane as mutating the hydrophobic patch restored MV production. Functionally, activation-evoked MVs from PR3-expressing cells induced a significantly larger respiratory burst in human neutrophils compared with control MVs. Conversely, MVs generated during apoptosis inhibited the basal respiratory burst in human neutrophils, and those generated from PR3-expressing cells hampered this inhibition. Given that membrane expression of PR3 is increased in patients with granulomatosis with polyangiitis, MVs generated from neutrophils expressing membrane PR3 may potentiate oxidative damage of endothelial cells and promote the systemic inflammation observed in this disease.
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Affiliation(s)
- Katherine R Martin
- From the INSERM, U1016, Institut Cochin, 75014 Paris, France, CNRS-UMR8104, 75014 Paris, France, Université Paris Descartes, Sorbonne Paris Cité, 75006 Paris, France, Center of Excellence, Labex Inflamex, 75013 Paris, France
| | - Chahrazade Kantari-Mimoun
- From the INSERM, U1016, Institut Cochin, 75014 Paris, France, CNRS-UMR8104, 75014 Paris, France, Université Paris Descartes, Sorbonne Paris Cité, 75006 Paris, France, Center of Excellence, Labex Inflamex, 75013 Paris, France
| | - Min Yin
- Université Paris Descartes, Sorbonne Paris Cité, 75006 Paris, France, INSERM, U970, Paris Cardiovascular Research Center PARCC, 75015 Paris, France
| | - Magali Pederzoli-Ribeil
- From the INSERM, U1016, Institut Cochin, 75014 Paris, France, CNRS-UMR8104, 75014 Paris, France, Université Paris Descartes, Sorbonne Paris Cité, 75006 Paris, France, Center of Excellence, Labex Inflamex, 75013 Paris, France
| | - Fanny Angelot-Delettre
- INSERM, UMR1098, Université Bourgogne Franche-Comté, Etablissement Français du Sang Bourgogne Franche-Comté, 25000 Besançon, France, Center of Excellence, Labex LipSTIC, 25000 Besançon, France
| | - Adam Ceroi
- INSERM, UMR1098, Université Bourgogne Franche-Comté, Etablissement Français du Sang Bourgogne Franche-Comté, 25000 Besançon, France, Center of Excellence, Labex LipSTIC, 25000 Besançon, France
| | - Cédric Grauffel
- Departments of Informatics and Molecular Biology, University of Bergen, 5008 Bergen, Norway
| | - Marc Benhamou
- Center of Excellence, Labex Inflamex, 75013 Paris, France, INSERM U1149/CNRS ERL8252, Université Paris-Diderot, 75018 Paris, France
| | - Nathalie Reuter
- Departments of Informatics and Molecular Biology, University of Bergen, 5008 Bergen, Norway
| | - Philippe Saas
- INSERM, UMR1098, Université Bourgogne Franche-Comté, Etablissement Français du Sang Bourgogne Franche-Comté, 25000 Besançon, France, Center of Excellence, Labex LipSTIC, 25000 Besançon, France
| | - Philippe Frachet
- Université Grenoble Alpes, Institut de Biologie Structurale (IBS), 38044 Grenoble, France, CNRS, IBS, 38044 Grenoble, France, and Commissariat à l'Energie Atomique, IBS, 38000 Grenoble, France
| | - Chantal M Boulanger
- Université Paris Descartes, Sorbonne Paris Cité, 75006 Paris, France, INSERM, U970, Paris Cardiovascular Research Center PARCC, 75015 Paris, France
| | - Véronique Witko-Sarsat
- From the INSERM, U1016, Institut Cochin, 75014 Paris, France, CNRS-UMR8104, 75014 Paris, France, Université Paris Descartes, Sorbonne Paris Cité, 75006 Paris, France, Center of Excellence, Labex Inflamex, 75013 Paris, France,
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12
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Pathak S, Kumar KR, Kanta H, Carr-Johnson F, Han J, Bashmakov A, Faure L, Ding H, Vanarsa K, Khan S, Li QZ, Chapman K, Wakeland EK, Mohan C. Fatty Acid Amide Hydrolase Regulates Peripheral B Cell Receptor Revision, Polyreactivity, and B1 Cells in Lupus. THE JOURNAL OF IMMUNOLOGY 2016; 196:1507-16. [DOI: 10.4049/jimmunol.1500291] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Accepted: 12/07/2015] [Indexed: 01/26/2023]
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13
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Two types of BCR interactions are positively selected during leukemia development in the Eμ-TCL1 transgenic mouse model of CLL. Blood 2015; 125:1578-88. [PMID: 25564405 DOI: 10.1182/blood-2014-07-587790] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Chronic lymphocytic leukemia (CLL) is a common B-cell malignancy characterized by a highly variable course and outcome. The disease is believed to be driven by B-cell receptor (BCR) signals generated by external antigens and/or cell-autonomous BCR interactions, but direct in vivo evidence for this is still lacking. To further define the role of the BCR pathway in the development and progression of CLL, we evaluated the capacity of different types of antigen/BCR interactions to induce leukemia in the Eμ-TCL1 transgenic mouse model. We show that cell autonomous signaling capacity is a uniform characteristic of the leukemia-derived BCRs and represents a prerequisite for CLL development. Low-affinity BCR interactions with autoantigens generated during apoptosis are also positively selected, suggesting that they contribute to the pathogenesis of the disease. In contrast, high-affinity BCR interactions are not selected, regardless of antigen form or presentation. We also show that the capacity of the leukemic cells to respond to cognate antigen correlates inversely with time to leukemia development, suggesting that signals induced by external antigen increase the aggressiveness of the disease. Collectively, these findings provide in vivo evidence that the BCR pathway drives the development and can influence the clinical course of CLL.
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14
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Salem D, Subang R, Okazaki Y, Laplante P, Levine JS, Kuwana M, Rauch J. β2-Glycoprotein I-specific T cells are associated with epitope spread to lupus-related autoantibodies. J Biol Chem 2015; 290:5543-55. [PMID: 25555913 DOI: 10.1074/jbc.m114.619817] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Systemic lupus erythematosus (SLE) is a prototypic model for B cell epitope spread in autoimmunity. Autoantibodies to numerous and molecularly distinct self-antigens emerge in a sequential manner over several years, leading to disease manifestations. Among the earliest autoantibodies to appear are those targeting the apoptotic cell-binding protein β2-glycoprotein I (β2GPI). Notably, mice immunized with β2GPI and LPS display a remarkably similar pattern of autoantibody emergence to that seen in human SLE. Here, we used this model to investigate whether epitope spread to SLE-related autoantibodies is associated with a unique or limited β2GPI-specific T cell response. We ask whether MHC class II haplotype and its associated T cell epitope restriction impact epitope spread to SLE-related autoantibodies. We found that β2GPI/LPS-immunized mice produced similar SLE-related autoantibody profiles regardless of their β2GPI T cell epitope specificity or MHC class II haplotype. Although β2GPI T cell epitope specificity was clearly determined by MHC class II haplotype, a number of different β2GPI T cell epitopes were associated with epitope spread to SLE-related autoantibodies. Notably, one β2GPI T cell epitope (peptide 23, NTGFYLNGADSAKCT) was also recognized by T cells from an HLA-DRB1*0403(+) autoimmune patient. These data suggest that the generation of a β2GPI-reactive T cell response is associated with epitope spread to SLE-related autoantibodies, independent of epitope specificity or MHC class II restriction. On the basis of these findings, we propose that factors enabling a β2GPI-reactive T cell response may predispose individuals to the development of SLE-related autoantibodies independent of their MHC class II haplotype.
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Affiliation(s)
- David Salem
- From the Division of Rheumatology, Department of Medicine, Research Institute of the McGill University Health Centre, Montreal, Quebec H3G 1A4, Canada
| | - Rebecca Subang
- From the Division of Rheumatology, Department of Medicine, Research Institute of the McGill University Health Centre, Montreal, Quebec H3G 1A4, Canada
| | - Yuka Okazaki
- the Division of Rheumatology, Department of Internal Medicine, Keio University School of Medicine, Tokyo 160-8582, Japan
| | - Patrick Laplante
- From the Division of Rheumatology, Department of Medicine, Research Institute of the McGill University Health Centre, Montreal, Quebec H3G 1A4, Canada
| | - Jerrold S Levine
- the Section of Nephrology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois 60612, and the Section of Nephrology, Department of Medicine, Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois 60612
| | - Masataka Kuwana
- the Division of Rheumatology, Department of Internal Medicine, Keio University School of Medicine, Tokyo 160-8582, Japan
| | - Joyce Rauch
- From the Division of Rheumatology, Department of Medicine, Research Institute of the McGill University Health Centre, Montreal, Quebec H3G 1A4, Canada,
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15
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Integrin CD11b negatively regulates BCR signalling to maintain autoreactive B cell tolerance. Nat Commun 2014; 4:2813. [PMID: 24264377 DOI: 10.1038/ncomms3813] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2013] [Accepted: 10/24/2013] [Indexed: 12/14/2022] Open
Abstract
A variant of the integrin-α-M (CD11b) gene has been linked to the pathogenesis of systemic lupus erythematosus. However, how this genotype results in the lupus phenotype is not fully understood. Here we show that autoreactive B cells lacking CD11b exhibit a hyperproliferative response to B cell receptor (BCR) crosslinking and enhanced survival. In vivo engagement of BCR in CD11b-deficient mice leads to increased autoAb production and kidney Ig deposition. In addition, CD11b-deficient autoreactive B cells have decreased tyrosine phosphorylation including Lyn and CD22 with decreased phosphatase SHP-1 recruitment but increased calcium influx. Results obtained using B cells transfected with the wild type or rs1143679 lupus-associated variant of CD11b suggest that this mutation completely abrogates the regulatory effect of CD11b on BCR signalling. This is through disruption of CD22-CD11b direct binding. These results reveal a previously unrecognized role of CD11b in maintaining autoreactive B cell tolerance.
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16
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Sang A, Zheng YY, Morel L. Contributions of B cells to lupus pathogenesis. Mol Immunol 2013; 62:329-38. [PMID: 24332482 DOI: 10.1016/j.molimm.2013.11.013] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2013] [Revised: 10/14/2013] [Accepted: 11/14/2013] [Indexed: 01/09/2023]
Abstract
Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by the production of autoantibodies. This review summarizes first the results obtained in the mouse that have revealed how B cell tolerance is breached in SLE. We then review the B cell subsets, in addition to the autoAb producing cells, which contribute to SLE pathogenesis, focusing on marginal zone B cells, B-1 cells and regulatory B cells. Finally, we review the interactions between B cells and other immune cells that have been implicated in SLE, such as dendritic cells, macrophages, neutrophils and T cells.
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Affiliation(s)
- Allison Sang
- Department of Pathology, Immunology, and Laboratory Medicine, University of Florida, Gainesville, FL 32610, USA
| | - Ying-Yi Zheng
- Department of Pathology, Immunology, and Laboratory Medicine, University of Florida, Gainesville, FL 32610, USA
| | - Laurence Morel
- Department of Pathology, Immunology, and Laboratory Medicine, University of Florida, Gainesville, FL 32610, USA.
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17
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Stolp J, Mariño E, Batten M, Sierro F, Cox SL, Grey ST, Silveira PA. Intrinsic molecular factors cause aberrant expansion of the splenic marginal zone B cell population in nonobese diabetic mice. THE JOURNAL OF IMMUNOLOGY 2013; 191:97-109. [PMID: 23740954 DOI: 10.4049/jimmunol.1203252] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Marginal zone (MZ) B cells are an innate-like population that oscillates between MZ and follicular areas of the splenic white pulp. Differentiation of B cells into the MZ subset is governed by BCR signal strength and specificity, NF-κB activation through the B cell-activating factor belonging to the TNF family (BAFF) receptor, Notch2 signaling, and migration signals mediated by chemokine, integrin, and sphingosine-1-phosphate receptors. An imbalance in splenic B cell development resulting in expansion of the MZ subset has been associated with autoimmune pathogenesis in various murine models. One example is the NOD inbred mouse strain, in which MZ B cell expansion has been linked to development of type 1 diabetes and Sjögren's syndrome. However, the cause of MZ B cell expansion in this strain remains poorly understood. We have determined that increased MZ B cell development in NOD mice is independent of T cell autoimmunity, BCR specificity, BCR signal strength, and increased exposure to BAFF. Rather, mixed bone marrow chimeras showed that the factor(s) responsible for expansion of the NOD MZ subset is B cell intrinsic. Analysis of microarray expression data indicated that NOD MZ and precursor transitional 2-MZ subsets were particularly dysregulated for genes controlling cellular trafficking, including Apoe, Ccbp2, Cxcr7, Lgals1, Pla2g7, Rgs13, S1pr3, Spn, Bid, Cd55, Prf1, and Tlr3. Furthermore, these B cell subsets exhibited an increased steady state dwell time within splenic MZ areas. Our data therefore reveal that precursors of mature B cells in NOD mice exhibit an altered migration set point, allowing increased occupation of the MZ, a niche favoring MZ B cell differentiation.
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Affiliation(s)
- Jessica Stolp
- Garvan Institute of Medical Research, Immunology Program, Darlinghurst, New South Wales 2010, Australia
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18
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Ravishankar B, McGaha TL. O death where is thy sting? Immunologic tolerance to apoptotic self. Cell Mol Life Sci 2013; 70:3571-89. [PMID: 23377225 DOI: 10.1007/s00018-013-1261-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2012] [Revised: 12/14/2012] [Accepted: 01/03/2013] [Indexed: 12/22/2022]
Abstract
In higher organisms, innate scavenging cells maintain physiologic homeostasis by removal of the billions of apoptotic cells generated on a daily basis. Apoptotic cell removal requires efficient recognition and uptake by professional and non-professional phagocytic cells, which are governed by an array of soluble and apoptotic cell-integral signals resulting in immunologically silent clearance. While apoptosis is associated with profound suppression of adaptive and innate inflammatory immunity, we have only begun to scratch the surface in understanding how immunologic tolerance to apoptotic self manifest at either the molecular or cellular level. In the last 10 years, data has emerged implicating professional phagocytes, most notably stromal macrophages and CD8α(+)CD103(+) dendritic cells, as critical in initiation of the regulatory cascade that will ultimately lead to long-term whole-animal immune tolerance. Importantly, recent work by our lab and others has shown that alterations in apoptotic cell perception by the innate immune system either by removal of critical phagocytic sentinels in secondary lymphoid organs or blockage of immunosuppressive pathways leads to pronounced inflammation with a breakdown of tolerance towards self. This challenges the paradigm that apoptotic cells are inherently immunosuppressive, suggesting that apoptotic cell tolerance is a "context-dependent" event.
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Affiliation(s)
- Buvana Ravishankar
- Cancer Immunology, Inflammation, and Tolerance Program, GRU Cancer Center, Georgia Regents University, Building CN4143, 1120 15th Street, Augusta, GA, 30904, USA
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19
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Lee SR, Rutan JA, Monteith AJ, Jones SZ, Kang SA, Krum KN, Kilmon MA, Roques JR, Wagner NJ, Clarke SH, Vilen BJ. Receptor cross-talk spatially restricts p-ERK during TLR4 stimulation of autoreactive B cells. THE JOURNAL OF IMMUNOLOGY 2012; 189:3859-68. [PMID: 22984080 DOI: 10.4049/jimmunol.1200940] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
To maintain tolerance, autoreactive B cells must regulate signal transduction from the BCR and TLRs. We recently identified that dendritic cells and macrophages regulate autoreactive cells during TLR4 activation by releasing IL-6 and soluble CD40 ligand (sCD40L). These cytokines selectively repress Ab secretion from autoreactive, but not antigenically naive, B cells. How IL-6 and sCD40L repress autoantibody production is unknown. In this work, we show that IL-6 and sCD40L are required for low-affinity/avidity autoreactive B cells to maintain tolerance through a mechanism involving receptor cross-talk between the BCR, TLR4, and the IL-6R or CD40. We show that acute signaling through IL-6R or CD40 integrates with chronic BCR-mediated ERK activation to restrict p-ERK from the nucleus and represses TLR4-induced Blimp-1 and XBP-1 expression. Tolerance is disrupted in 2-12H/MRL/lpr mice where IL-6 and sCD40L fail to spatially restrict p-ERK and fail to repress TLR4-induced Ig secretion. In the case of CD40, acute signaling in B cells from 2-12H/MRL/lpr mice is intact, but the chronic activation of p-ERK emanating from the BCR is attenuated. Re-establishing chronically active ERK through retroviral expression of constitutively active MEK1 restores tolerance upon sCD40L, but not IL-6, stimulation, indicating that regulation by IL-6 requires another signaling effector. These data define the molecular basis for the regulation of low-affinity autoreactive B cells during TLR4 stimulation; they explain how autoreactive but not naive B cells are repressed by IL-6 and sCD40L; and they identify B cell defects in lupus-prone mice that lead to TLR4-induced autoantibody production.
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Affiliation(s)
- Sang-Ryul Lee
- Department of Microbiology and Immunology, University of North Carolina, Chapel Hill, NC 27599, USA
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20
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Shao WH, Zhen Y, Finkelman FD, Eisenberg RA, Cohen PL. Intrinsic unresponsiveness of Mertk-/- B cells to chronic graft-versus-host disease is associated with unmodulated CD1d expression. J Autoimmun 2012; 39:412-9. [PMID: 22854104 DOI: 10.1016/j.jaut.2012.07.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2012] [Revised: 07/02/2012] [Accepted: 07/04/2012] [Indexed: 01/17/2023]
Abstract
Activation and migration of marginal zone B (MZB) cells into follicular (FO) regions of the spleen has been proposed as one of the mechanisms that regulate the development of autoreactive B cells. The mer receptor tyrosine kinase (Mertk) mediates apoptotic cell clearance and regulates activation and cytokine secretion. In the well-studied class II chronic GVH model of bm12 cells into B6 hosts, we observed that Mertk deficient B6 mice did not generate autoantibodies in response to this allogeneic stimulus. We posited that Mertk is important in MHC-II-mediated B cell signaling. In the present study, we show that B cells from Mertk(-/-) mice but not WT B6 mice exhibited decreased calcium mobilization and tyrosine phosphorylation when stimulated by MHC-II cross-linking. The finding that Mertk was important for class II signaling in B cells was further supported by the preponderance of a-allotype autoantibodies in cGVH in RAG-KO mice reconstituted with a mixture of bone marrow from Mertk(-/-) mice (b-allotype) and C20 mice (a-allotype). MZB cells from Mertk(-/-) mice were unable to down regulate surface CD1d expression and subsequent inclusion in the MZ, associated with significantly lower germinal center responses compared to MZB cells from WT. Moreover, Mertk(-/-) mice treated with an anti-CD1d down regulating antibody responded significantly to bm12 cells, while no response was observed in Mertk(-/-) mice treated with control antibodies. Taken together, these findings extend the role of Mertk to include CD1d down regulation on MZB cells, a potential mechanism limiting B cell activation in cGVH.
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Affiliation(s)
- Wen-Hai Shao
- Section of Rheumatology, Department of Medicine, Temple University, Philadelphia PA 19140, USA
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21
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Apoptotic marginal zone deletion of anti-Sm/ribonucleoprotein B cells. Proc Natl Acad Sci U S A 2012; 109:7811-6. [PMID: 22547827 DOI: 10.1073/pnas.1204509109] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
CD40L is excessively produced in both human and murine lupus and plays a role in lupus pathogenesis. To address how excess CD40L induces autoantibody production, we crossed CD40L-transgenic mice with the anti-DNA H-chain transgenic mouse lines 3H9 and 56R, well-characterized models for studying B-cell tolerance to nuclear antigens. Excess CD40L did not induce autoantibody production in 3H9 mice in which anergy maintains self-tolerance, nor did it perturb central tolerance, including deletion and receptor editing, of anti-DNA B cells in 56R mice. In contrast, CD40L/56R mice restored a large number of marginal zone (MZ) B cells reactive to Sm/ribonucleoprotein (RNP) and produced autoantibody, whereas these B cells were deleted by apoptosis in MZ of 56R mice. Thus, excess CD40L efficiently blocked tolerance of Sm/RNP-reactive MZ B cells, leading to production of anti-Sm/RNP antibody implicated in the pathogenesis of lupus. These results suggest that self-reactive B cells such as anti-Sm/RNP B cells, which somehow escape tolerance in the bone marrow and migrate to MZ, are tolerized by apoptotic deletion in MZ and that a break in this tolerance may play a role in the pathogenesis of lupus.
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22
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Sang A, Yin Y, Zheng YY, Morel L. Animal Models of Molecular Pathology. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2012; 105:321-70. [DOI: 10.1016/b978-0-12-394596-9.00010-x] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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23
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A tolerogenic role for Toll-like receptor 9 is revealed by B-cell interaction with DNA complexes expressed on apoptotic cells. Proc Natl Acad Sci U S A 2011; 109:887-92. [PMID: 22207622 DOI: 10.1073/pnas.1109173109] [Citation(s) in RCA: 114] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Intracellular protein complexes containing nucleic acids are common targets of autoantibodies in many autoimmune diseases. Central tolerance to these antigens is incomplete, yet nucleosomal DNA is expressed on the surface of cells dying by apoptosis. It is commonly believed that autoimmunity is prevented by the rapid uptake of apoptotic cells (ACs) by neighbors or professional phagocytes to which they deliver anti-inflammatory signals. Self-reactive, innate-like B cells contact and are selected by intracellular antigens expressed on ACs; however, how self-tolerance is maintained is not well understood. Here we report that IL-10 production by B cells, stimulated by contact with ACs, results from the engagement of Toll-like receptor 9 (TLR9) within the B cell after recognition of DNA-containing complexes on the surface of ACs. Until now, TLR9 ligation has been considered an inflammatory signal, but we have confirmed a hitherto unexpected immunoregulatory role by demonstrating the absence of the protective effect of ACs during experimental autoimmune encephalitis (EAE) in TLR9-deficient mice. Human circulating CD27(+) B cells also respond to DNA-bearing ACs, but not to DNase-treated cells, by secreting IL-10. Chronic autoimmune disease may arise if this tolerance mechanism is not reimposed after episodes of inflammation, or if the regulatory B-cell response is subverted.
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24
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Wen X, Yang JQ, Kim PJ, Singh RR. Homeostatic regulation of marginal zone B cells by invariant natural killer T cells. PLoS One 2011; 6:e26536. [PMID: 22046304 PMCID: PMC3202546 DOI: 10.1371/journal.pone.0026536] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2011] [Accepted: 09/28/2011] [Indexed: 11/18/2022] Open
Abstract
Marginal zone B cells (MZB) mount a rapid antibody response, potently activate naïve T cells, and are enriched in autoreactive B cells. MZBs express high levels of CD1d, the restriction element for invariant natural killer T cells (iNKT). Here, we examined the effect of iNKT cells on MZB cell activation and numbers in vitro and in vivo in normal and autoimmune mice. Results show that iNKT cells activate MZBs, but restrict their numbers in vitro and in vivo in normal BALB/c and C57/BL6 mice. iNKT cells do so by increasing the activation-induced cell death and curtailing proliferation of MZB cells, whereas they promote the proliferation of follicular B cells. Sorted iNKT cells can directly execute this function, without help from other immune cells. Such MZB regulation by iNKTs is mediated, at least in part, via CD1d on B cells in a contact-dependent manner, whereas iNKT-induced proliferation of follicular B cells occurs in a contact- and CD1d-independent manner. Finally, we show that iNKT cells reduce 'autoreactive' MZB cells in an anti-DNA transgenic model, and limit MZB cell numbers in autoimmune-prone (NZB×NZW)F1 and non-obese diabetic mice, suggesting a potentially new mechanism whereby iNKT cells might regulate pathologic autoimmunity. Differential regulation of follicular B cells versus potentially autoreactive MZBs by iNKT cells has important implications for autoimmune diseases as well as for conditions that require a rapid innate B cell response.
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Affiliation(s)
- Xiangshu Wen
- Autoimmunity and Tolerance Laboratory, Division of Rheumatology, Department of Medicine, David Geffen School of Medicine at University of California Los Angeles, Los Angeles, California, United States of America
| | - Jun-Qi Yang
- University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
- Jiangsu Institute of Parasitic Diseases, Wuxi, Jiangsu, China
| | - Peter J. Kim
- Autoimmunity and Tolerance Laboratory, Division of Rheumatology, Department of Medicine, David Geffen School of Medicine at University of California Los Angeles, Los Angeles, California, United States of America
| | - Ram Raj Singh
- Autoimmunity and Tolerance Laboratory, Division of Rheumatology, Department of Medicine, David Geffen School of Medicine at University of California Los Angeles, Los Angeles, California, United States of America
- Department of Pathology and Laboratory Medicine, University of California Los Angeles, Los Angeles, California, United States of America
- Jonsson Comprehensive Cancer Center, University of California Los Angeles, Los Angeles, California, United States of America
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25
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Samuelson EM, Laird RM, Maue AC, Rochford R, Hayes SM. Blk haploinsufficiency impairs the development, but enhances the functional responses, of MZ B cells. Immunol Cell Biol 2011; 90:620-9. [PMID: 21894171 DOI: 10.1038/icb.2011.76] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Blk was identified two decades ago as a B-cell-specific member of the Src family of tyrosine kinases. Recent studies, however, have discovered that Blk is expressed in many cell types outside of the B lineage, including early thymic precursors, interleukin-17-producing γδ T cells and pancreatic β-cells. In light of these recent discoveries, we performed a more comprehensive analysis of Blk expression patterns in hematopoietic cells and found that Blk is differentially expressed in mature B-cell subsets, with marginal zone (MZ) B cells expressing high levels, B1 B cells expressing intermediate-to-high levels and follicular (FO) B cells expressing low levels of Blk. To determine whether these differences in Blk expression levels reflected differential requirements for Blk in MZ, B1 and FO B-cell development, we analyzed the effects of reducing and eliminating Blk expression on B-cell development. We report that both Blk haploinsufficiency and Blk deficiency impaired the generation of MZ B cells. Moreover, although there were fewer MZ B cells in Blk(+/-) and Blk(-/-) mice as compared with Blk(+/+) mice, Blk-mutant MZ B cells were hyper-responsive to B-cell receptor stimulation, both in vitro and in vivo. Thus, this study has revealed a previously unappreciated role for Blk in the development and activation of MZ B cells.
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Affiliation(s)
- Elizabeth M Samuelson
- Department of Microbiology and Immunology, State University of New York Upstate Medical University, Syracuse, NY 13210, USA
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26
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Yoshida T, Mei H, Dörner T, Hiepe F, Radbruch A, Fillatreau S, Hoyer BF. Memory B and memory plasma cells. Immunol Rev 2010; 237:117-39. [PMID: 20727033 DOI: 10.1111/j.1600-065x.2010.00938.x] [Citation(s) in RCA: 215] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Vaccination provides a powerful means to control infections. It exploits and exemplifies the ability of the immune system to preserve the information that a specific pathogen has been encountered in the past. The cells and molecular mechanisms of immunological memory are still being discussed controversially. Here, we review the current concepts of memory B cells, the signals involved in their maintenance, and their role in enhanced secondary reactions. Memory plasma cells, secreting protective antibodies over lifetime, have been recognized only recently. Their characterization as cells resting in terms of proliferation and migration, and surviving in dedicated stromal niches, in the absence of antigen, has generated new concepts of how memory cells in general are organized by stroma cells, the 'resting memory'. In autoimmunity and chronic inflammation, memory B cells and memory plasma cells can be essential players, and they require special attention, as they do not respond to most conventional therapies. Their selective targeting will depend on a molecular understanding of their lifestyle.
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Affiliation(s)
- Taketoshi Yoshida
- Charité Centre 12, Clinic for Internal Medicine, Rheumatology, Clinical Immunology, Charité University Hospital Berlin, Berlin, Germany
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27
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Schroeder HW, Zemlin M, Khass M, Nguyen HH, Schelonka RL. Genetic control of DH reading frame and its effect on B-cell development and antigen-specifc antibody production. Crit Rev Immunol 2010; 30:327-44. [PMID: 20666706 DOI: 10.1615/critrevimmunol.v30.i4.20] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The power of the adaptive immune system to identify novel antigens depends on the ability of lymphocytes to create antigen receptors with diverse antigen-binding sites. For immunoglobulins, CDR (complementarity-determining region)-H3 lies at the center of the antigen-binding site, where it often plays a key role in antigen binding. It is created de novo by VDJ rearrangement and is thus the focus for rearrangement-dependent diversity. CDR-H3 is biased for the inclusion of tyrosine. In seeking to identify the mechanisms controlling CDR-H3 amino acid content, we observed that the coding sequence of DH gene segments demonstrate conservation of reading frame (RF)-specific sequence motifs, with RF1 enriched for tyrosine and depleted of hydrophobic and charged amino acids. Use of DH RF1 in functional VDJ transcripts is preferred from the earliest stages of B-cell development, "pushing" CDR-H3 to include specific categories of tyrosine-enriched antigen-binding sites. With development and maturation, the composition of the CDR-H3 repertoire appears to be pulled into a more refined specific range. Forcing the use of alternative DH RFs by means of gene targeting alters the expressed repertoire, enriching alternative sequence categories. This change in the repertoire variably affects antibody production and the development of specific B-cell subsets.
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Affiliation(s)
- Harry W Schroeder
- Department of Medicine, University of Alabama at Birmingham, 35294-2182, USA.
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28
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Shao WH, Kuan AP, Wang C, Abraham V, Waldman MA, Vogelgesang A, Wittenburg G, Choudhury A, Tsao PY, Miwa T, Eisenberg RA, Cohen PL. Disrupted Mer receptor tyrosine kinase expression leads to enhanced MZ B-cell responses. J Autoimmun 2010; 35:368-74. [PMID: 20822883 DOI: 10.1016/j.jaut.2010.08.001] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2010] [Revised: 08/07/2010] [Accepted: 08/09/2010] [Indexed: 11/19/2022]
Abstract
Control of lymphocyte homeostasis is essential to ensure efficient immune responses and to prevent autoimmunity. Splenic marginal zone B cells are important producers of autoantibodies, and are subject to stringent tolerance mechanisms to prevent autoimmunity. In this paper, we explore the role of the Mer tyrosine kinase (Mertk) in regulating autoreactive B cells. This receptor tyrosine kinase serves to bind apoptotic cells, to mediate their phagocytosis, and to regulate subsequent cytokine production. Mice lacking Mertk suffer from impaired apoptotic cell clearance and develop a lupus-like autoimmune syndrome. Here we show that such Mertk-KO mice have expanded numbers of splenic marginal zone B cells. Mertk-KO mice bearing a DNA-specific immunoglobulin heavy-chain transgene (3H9) produced anti-DNA antibodies that appeared to be secreted largely by marginal zone B cells. Finally, Mertk-KO mice developed greater antibody responses after NP-Ficoll immunization than their B6 counterparts. Taken together, our data show that Mertk has a major effect on the development of the marginal zone B-cell compartment. Mertk is also important in establishing DNA-specific B-cell tolerance in 3H9 anti-DNA transgenic mice.
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Affiliation(s)
- Wen-Hai Shao
- Section of Rheumatology, Department of Medicine, Temple University, USA
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Williams JC, Wagner NJ, Earp HS, Vilen BJ, Matsushima GK. Increased hematopoietic cells in the mertk-/- mouse peritoneal cavity: a result of augmented migration. THE JOURNAL OF IMMUNOLOGY 2010; 184:6637-48. [PMID: 20483720 DOI: 10.4049/jimmunol.0902784] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The peritoneal cavity is recognized as an important site for autoreactive B cells prior to their transit to other immune tissues; however, little is known of the genes that may regulate this process. Mice lacking the receptor tyrosine kinase, Mertk, display a lupus-like autoimmune phenotype with splenomegaly and high autoantibodies titers. In this study, we investigate whether Mertk regulates the composition of peritoneal cells that favor an autoimmune phenotype. We found an increase in the number of macrophages, dendritic cells (DCs), plasmacytoid DCs, T cells, and B cells in the peritoneal cavity of mertk-/- mice when compared with wild-type mice. This disparity in cell numbers was not due to changes in cell proliferation or cell death. In adoptive transfer experiments, we showed an increase in migration of labeled donor cells into the mertk-/- peritoneal cavity. In addition, bone marrow chimeric mice showed hematopoietic-derived factors were also critical for T cell migration. Consistent with this migration and the increase in the number of cells, we identified elevated expression of CXCL9, its receptor CXCR3, and IL-7R on peritoneal cells from mertk-/- mice. To corroborate the migratory function of CXCR3 on cells, the depletion of CXCR3 donor cells significantly reduced the number of adoptively transferred cells that entered into the peritoneum of mertk-/- mice. This control of peritoneal cells numbers correlated with autoantibody production and was exclusively attributed to Mertk because mice lacking other family members, Axl or Tyro 3, did not display dysregulation in peritoneal cell numbers or the autoimmune phenotype.
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Affiliation(s)
- Julie C Williams
- Curriculum in Oral Biology, Department of Microbiology and Immunology, University of North Carolina Neuroscience Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
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Gohlke PR, Williams JC, Vilen BJ, Dillon SR, Tisch R, Matsushima GK. The receptor tyrosine kinase MerTK regulates dendritic cell production of BAFF. Autoimmunity 2009; 42:183-97. [PMID: 19301199 DOI: 10.1080/08916930802668586] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The MerTK receptor tyrosine kinase is an important negative regulator of dendritic cell function and is required to prevent B cell autoimmunity in vivo. It is not currently known however, if any causal relationship exists between these two aspects of MerTK function. We sought to determine if dendritic cells (DC) from mice lacking MerTK (mertk(- / - ) mice) have characteristics that may aid in the development of B cell autoimmunity. Specifically, we found that mertk(- / - ) mice contain an elevated number of splenic DC, and this population contains an elevated proportion of cells secreting the critical B cell pro-survival factor, B cell activating factor (BAFF). Elevated numbers of BAFF-secreting cells were also detected among mertk(- / - ) bone marrow-derived dendritic cell (BMDC) populations. This was observed in both resting BMDC, and BMDC stimulated with lipopolysaccharide (LPS) or treated with exogenous apoptotic cells. We also found that DC in general have a pro-survival effect on resting B cells in co-culture. However, despite containing more BAFF-secreting cells, mertk(- / - ) BMDC were not superior to C57BL/6 or baff-deficient BMDC at promoting B cell survival. Furthermore, using decoy receptors, we show that DC may promote B cell survival and autoimmunity through a BAFF-and a proliferation-inducing ligand-independent mechanism.
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Affiliation(s)
- P R Gohlke
- Department of Microbiology and Immunology, University of North Carolina-CH, Chapel Hill, 27599, USA
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31
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Diz R, McCray SK, Clarke SH. B cell receptor affinity and B cell subset identity integrate to define the effectiveness, affinity threshold, and mechanism of anergy. THE JOURNAL OF IMMUNOLOGY 2008; 181:3834-40. [PMID: 18768837 DOI: 10.4049/jimmunol.181.6.3834] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
In this study we show that BCR affinity and subset identity make unique contributions to anergy. Analysis of anti-Smith (Sm) B cells of different affinities indicates that increasing affinity improves anergy's effectiveness while paradoxically increasing the likelihood of marginal zone (MZ) and B-1 B cell differentiation rather than just follicular (FO) B cell differentiation. Subset identity in turn determines the affinity threshold and mechanism of anergy. Subset-specific affinity thresholds for anergy induction allow discordant regulation of low-affinity anti-Sm FO and MZ B cells and could account for the higher frequency of autoreactive MZ B cells than that of FO B cells in normal mice. The mechanism of anergy changes during differentiation and differs between subsets. This is strikingly illustrated by the observation that blockade of BCR-mediated activation of FO and MZ B cells occurs at different levels in the signaling cascade. Thus, attributes unique to B cells of each subset integrate with signals from the BCR to determine the effectiveness, affinity threshold, and mechanism of anergy.
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Affiliation(s)
- Ramiro Diz
- Department of Microbiology and Immunology, University of North Carolina, Chapel Hill, NC 27599, USA
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32
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Fossati-Jimack L, Cortes-Hernandez J, Norsworthy PJ, Cook HT, Walport MJ, Botto M. Regulation of B cell tolerance by 129-derived chromosome 1 loci in C57BL/6 mice. ACTA ACUST UNITED AC 2008; 58:2131-41. [PMID: 18576325 PMCID: PMC2658014 DOI: 10.1002/art.23553] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
OBJECTIVE Systemic lupus erythematosus is a multifactorial disease with a strong genetic component. Previous studies have shown that a 129-derived chromosome 1 interval (Sle16) on the C57BL/6 (B6) background is sufficient to induce humoral autoimmunity. The aim of the present study was to elucidate the mechanisms by which this locus contributes to the loss of peripheral tolerance. METHODS Anti-single-stranded DNA (anti-ssDNA)-knockin transgenic mice (V(H)3H9R/Vkappa8R and V(H)3H9R) were crossed with a B6 congenic line named B6.129chr1b that carries the Sle16 locus. A parallel study of a gene-targeted animal, whose mutated gene is located within the 129chr1b interval on chromosome 1, was also performed. RESULTS The combination of V(H)3H9R/Vkappa8R with the 129chr1b interval resulted in impaired B cell anergy, and transgenic IgM and IgG anti-ssDNA antibodies were found in the circulation. The presence of IgG2a(a) anti-ssDNA and IgM(a) anti-Sm antibodies in sera indicated that the autoreactive transgenic B cells underwent class switching and epitope spreading. The 129chr1b locus appeared to have a dominant effect, since transgenic antibodies were also detected in mice carrying a single allele. The gene-targeted animals showed a similar phenotype. CONCLUSION The presence of a single 129chr1b locus on the B6 background impaired B cell anergy, prevented deletion of anti-DNA transgenic B cells, and induced receptor revision. The findings of this study also emphasize that the autoimmune phenotype observed in mice with targeted genes located on chromosome 1 may simply arise from epistatic interactions between the 129 and B6 parental strains.
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Affiliation(s)
- Liliane Fossati-Jimack
- Molecular Genetics and Rheumatology Section, Faculty of Medicine, Imperial College, London, UK.
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Witsch EJ, Bettelheim E. Allelic and Isotypic Light Chain Inclusion in Peripheral B Cells from Anti-DNA Antibody Transgenic C57BL/6 and BALB/c Mice. THE JOURNAL OF IMMUNOLOGY 2008; 180:3708-18. [DOI: 10.4049/jimmunol.180.6.3708] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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35
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Abstract
Systemic lupus erythematosus (SLE) highlights the dangers of dysregulated B cells and the importance of initiating and maintaining tolerance. In addition to central deletion, receptor editing, peripheral deletion, receptor revision, anergy, and indifference, we have described a new mechanism of B cell tolerance wherein dendritic cells (DCs) and macrophages (MPhis) regulate autoreactive B cells during innate immune responses. In part, DCs and MPhis repress autoreactive B cells by releasing IL-6 and soluble CD40L (sCD40L). This mechanism is selective in that IL-6 and sCD40L do not affect Ig secretion by naïve cells during innate immune responses, allowing immunity in the absence of autoimmunity. In lupus-prone mice, DCs and MPhis are defective in secretion of IL-6 and sCD40L and cannot effectively repress autoantibody secretion suggesting that defects in DC/MPhi-mediated tolerance may contribute to the autoimmune phenotype. Further, these studies suggest that reconstituting DCs and MPhis in SLE patients might restore regulation of autoreactive B cells and provide an alternative to immunosuppressive therapies.
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Affiliation(s)
- Barbara J Vilen
- Department of Microbiology, University of North Carolina, CB 7290, Chapel Hill, NC 27599, USA.
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36
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Krieg AM, Vollmer J. Toll-like receptors 7, 8, and 9: linking innate immunity to autoimmunity. Immunol Rev 2007; 220:251-69. [DOI: 10.1111/j.1600-065x.2007.00572.x] [Citation(s) in RCA: 276] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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37
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Kilmon MA, Wagner NJ, Garland AL, Lin L, Aviszus K, Wysocki LJ, Vilen BJ. Macrophages prevent the differentiation of autoreactive B cells by secreting CD40 ligand and interleukin-6. Blood 2007; 110:1595-602. [PMID: 17712049 PMCID: PMC1952615 DOI: 10.1182/blood-2007-06-061648] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Activation of the innate immune system promotes polyclonal antibody secretion to eliminate invading pathogens. Inherent in this process is the potential to activate autoreactive B cells and induce autoimmunity. We showed previously that TLR-stimulated dendritic cells and macrophages regulate B cell tolerance to Smith antigen, in part through the secretion of interleukin-6 (IL-6). In this manuscript, we show that neutralization of IL-6 fails to abrogate macrophage-mediated repression and identify soluble CD40 ligand (CD40L) as a second repressive factor secreted by macrophages. CD40L selectively repressed Ig secretion by chronically antigen-experienced (anergic) immunoglobulin transgenic and nontransgenic B cells but not by transiently stimulated B cells. The importance of macrophages in maintaining B cell tolerance was apparent in lupus-prone MRL/lpr mice. Compared with C57BL/6 mice, macrophages from MRL/lpr mice were significantly less efficient at repressing immunoglobulin secretion coincident with diminished IL-6 and CD40 ligand production. These data indicate that macrophages regulate autoreactive B cells by secreting repressive factors that prohibit terminal differentiation of B cells. The regulation of autoreactive B cells by macrophages is diminished in lupus-prone mice suggesting a role in autoimmunity.
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Affiliation(s)
- Michelle A Kilmon
- Department of Microbiology and Immunology, Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, NC 27599, USA
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38
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Macrophages prevent the differentiation of autoreactive B cells by secreting CD40 ligand and interleukin-6. Blood 2007. [PMID: 17712049 DOI: 10.1182/blood-2006-12-061648] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Activation of the innate immune system promotes polyclonal antibody secretion to eliminate invading pathogens. Inherent in this process is the potential to activate autoreactive B cells and induce autoimmunity. We showed previously that TLR-stimulated dendritic cells and macrophages regulate B cell tolerance to Smith antigen, in part through the secretion of interleukin-6 (IL-6). In this manuscript, we show that neutralization of IL-6 fails to abrogate macrophage-mediated repression and identify soluble CD40 ligand (CD40L) as a second repressive factor secreted by macrophages. CD40L selectively repressed Ig secretion by chronically antigen-experienced (anergic) immunoglobulin transgenic and nontransgenic B cells but not by transiently stimulated B cells. The importance of macrophages in maintaining B cell tolerance was apparent in lupus-prone MRL/lpr mice. Compared with C57BL/6 mice, macrophages from MRL/lpr mice were significantly less efficient at repressing immunoglobulin secretion coincident with diminished IL-6 and CD40 ligand production. These data indicate that macrophages regulate autoreactive B cells by secreting repressive factors that prohibit terminal differentiation of B cells. The regulation of autoreactive B cells by macrophages is diminished in lupus-prone mice suggesting a role in autoimmunity.
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39
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Kumar KR, Mohan C. Understanding B-cell tolerance through the use of immunoglobulin transgenic models. Immunol Res 2007; 40:208-23. [DOI: 10.1007/s12026-007-8008-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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40
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Schiller M, Bekeredjian-Ding I, Heyder P, Blank N, Ho AD, Lorenz HM. Autoantigens are translocated into small apoptotic bodies during early stages of apoptosis. Cell Death Differ 2007; 15:183-91. [PMID: 17932498 DOI: 10.1038/sj.cdd.4402239] [Citation(s) in RCA: 152] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
A dysregulation of apoptosis or an ineffective clearance of apoptotic material is suspected to be involved in the pathogenesis of systemic lupus erythematodes. Subcellular fragments such as apoptotic bodies (ABs) have been recognized as modulators of intercellular communication and immune function. In this context, we have been interested whether nuclear and cytoplasmic antigens are relocated into ABs. In the present study, we characterized ABs isolated from apoptozing lymphoblasts. We found an accumulation of the linker-histone (histone 1) as well as the core-histones (histone 2A, histone 2B, histone 3, histone 4) in ABs. Further, they contained DNA, RNA and the ribonuclear protein La/SSB. Proteins such as cytochrome c, HSP 70, prohibitin, p53, nuclear matrix antigen or lamin B were excluded from ABs. The content of ABs differed from that observed in membrane microparticles isolated from viable cells. Formation of ABs occurred early during apoptosis. It was observed before DNA-degradation or phosphatidylserine exposure was detected. ABs were engulfed by monocyte-derived phagocytes. These findings suggest that immunogenic molecules are actively translocated into ABs followed by a rapid engulfment of the latter by environmental phagocytes. In autoimmune diseases, a defect in the clearance of ABs or AB formation may contribute to the development of autoimmunity.
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Affiliation(s)
- M Schiller
- Department of Medicine V, University of Heidelberg, Im Neuenheimer Feld 410, Heidelberg, Germany.
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41
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Choudhury A, Cohen PL, Eisenberg RA. Mature B Cells Preferentially Lose Tolerance in the Chronic Graft-versus-Host Disease Model of Systemic Lupus Erythematosus. THE JOURNAL OF IMMUNOLOGY 2007; 179:5564-70. [PMID: 17911643 DOI: 10.4049/jimmunol.179.8.5564] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Chronic graft-vs-host (cGVH) disease is a well-characterized systemic lupus erythematosus (SLE) model. Induction of cGVH in anti-DNA H chain knockin (3H9KI) transgenic mice results in specific activation of anti-dsDNA B cells. In this study, we show that B cells from 3H9KI mice were activated by cGVH even when adoptively transferred into irradiated JHT-/- recipients that lack endogenous B cells. This process of activation was reflected by high autoantibody titers and changes in phenotypic markers. We have used this system to characterize the particular B cell subsets that were responsible for secreting autoantibodies during cGVH response. We isolated splenic B cell subsets based on their expression of specific cell surface markers and used them in our adoptive transfer studies. We found that mature B cells were the most vulnerable to the allostimulus and were the major source of autoantibodies compared with immature B cells. The greater susceptibility of mature B cells to become activated and thereby lose tolerance was unanticipated and has implications for maintenance of peripheral tolerance and for the development of autoimmunity. Furthermore, of the mature B cells, marginal zone B cells were particularly responsible for mounting the initial response to the cGVH stimulus. This observation underscores the critical role of marginal zone B cells in activation and production of autoantibodies.
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Affiliation(s)
- Arpita Choudhury
- Department of Medicine, Division of Rheumatology, University of Pennsylvania, Philadelphia, PA 19104, USA
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42
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Fossati-Jimack L, Cortes-Hernandez J, Norsworthy PJ, Walport MJ, Cook HT, Botto M. C1q deficiency promotes the production of transgenic-derived IgM and IgG3 autoantibodies in anti-DNA knock-in transgenic mice. Mol Immunol 2007; 45:787-95. [PMID: 17675234 PMCID: PMC2080686 DOI: 10.1016/j.molimm.2007.06.162] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2007] [Accepted: 06/20/2007] [Indexed: 01/03/2023]
Abstract
C1q-deficient mice have been shown to develop a lupus-like disease and to display an impaired clearance of apoptotic cells that are enriched in lupus autoantigens. However, the role of C1q in the regulation of autoreactive B cells remains debatable. To explore this we crossed MRL/Mp C1q-deficient mice with knock-in transgenic (Tg) mice expressing an anti-ssDNA antibody (VH3H9R and VH3H9R/VLκ8R). Analysis of the VH3H9R mice showed that in the absence of C1q higher titres of Tg-derived IgM and IgG3 anti-ssDNA antibodies were detectable. In contrast, in the VH3H9R/VLκ8R C1q-deficient animals no increase in Tg antibody levels was observed. In both models the lack of C1q induced a marked reduction of marginal zone B cells and this was paralleled by a significant increase in the percentage of plasmocytes. Thus, one could postulate that in the absence of C1q the failure to clear efficiently dying cells provides an additional stimulus to the autoreactive Tg B cells resulting in their emigration from the marginal zone B cell compartment with subsequent increase in plasmocytes. However, the lack of C1q led to an increased production of Tg IgM and IgG3 antibodies only in VH3H9R mice indicating that additional genetic susceptibility factors are required to break self-tolerance.
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Affiliation(s)
- Liliane Fossati-Jimack
- Molecular Genetics & Rheumatology Section, Faculty of Medicine, Imperial College London, Hammersmith Campus, Du Cane Road, London W12 0NN, UK.
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Cambier JC, Gauld SB, Merrell KT, Vilen BJ. B-cell anergy: from transgenic models to naturally occurring anergic B cells? Nat Rev Immunol 2007; 7:633-43. [PMID: 17641666 PMCID: PMC3714009 DOI: 10.1038/nri2133] [Citation(s) in RCA: 259] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Anergy, a condition in which cells persist in the periphery but are unresponsive to antigen, is responsible for silencing many self-reactive B cells. Loss of anergy is known to contribute to the development of autoimmune diseases, including systemic lupus erythematosus and type 1 diabetes. Multiple transgenic mouse models have enabled the dissection of mechanisms that underlie anergy, and recently, anergic B cells have been identified in the periphery of wild-type mice. Heterogeneity of mechanistic concepts developed using model systems has complicated our understanding of anergy and its biological features. In this Review, we compare and contrast the salient features of anergic B cells with a view to developing unifying mechanistic hypotheses that explain their lifestyles.
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Affiliation(s)
- John C Cambier
- Department of Immunology, University of Colorado Health Science Center and National Jewish Medical Research Center, 1400 Jackson Street, Denver, Colorado 80206, USA.
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44
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Schelonka RL, Tanner J, Zhuang Y, Gartland GL, Zemlin M, Schroeder HW. Categorical selection of the antibody repertoire in splenic B cells. Eur J Immunol 2007; 37:1010-21. [PMID: 17345580 DOI: 10.1002/eji.200636569] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
In the bone marrow, the passage of developing B cells through critical checkpoints of differentiation is associated with a reduction of specific categories of CDR3 of the Ig heavy chain (CDR-H3), particularly those with excessive hydrophobic or charged amino acids and those with a length of eight or fewer residues. To gain insight into the role of CDR-H3 content in the development of B cells in the spleen, we compared the sequences of V(H)7183DJCmu transcripts from sorted transitional T1, marginal zone, and follicular B cell subsets to those expressed by immature IgM(+)IgD(-) and mature IgM(lo)IgD(hi) B cells in the bone marrow. Although differences in V(H) utilization were noted, the T1 CDR-H3 repertoire showed extensive similarity to that of immature bone marrow B cells, and the follicular CDR-H3 repertoire most resembled that of mature bone marrow B cells. Unlike the splenic follicular and bone marrow mature B cell CDR-H3 repertoires, the marginal zone B cell CDR-H3 repertoire retained both short and highly charged amino acid motifs, including those with two arginines. Our findings suggest that antigen binding sites containing specific categories of CDR-H3 sequence content may inhibit, permit, or even facilitate passage of the host B cell through critical checkpoints in peripheral as well as central development.
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Affiliation(s)
- Robert L Schelonka
- Department of Pediatrics, University of Alabama at Birmingham, Birmingham, AL 35233-1530, USA.
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45
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Levine JS, Subang R, Nasr SH, Fournier S, Lajoie G, Wither J, Rauch J. Immunization with an apoptotic cell-binding protein recapitulates the nephritis and sequential autoantibody emergence of systemic lupus erythematosus. THE JOURNAL OF IMMUNOLOGY 2006; 177:6504-16. [PMID: 17056583 PMCID: PMC3439500 DOI: 10.4049/jimmunol.177.9.6504] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The initial events predisposing to loss of tolerance in patients with systemic lupus erythematosus (SLE) are largely unknown, as are the events that precipitate the transition from preclinical to overt disease. We hypothesized that induction of murine SLE would require tipping the balance between tolerance and immunity in two ways: 1) an immunogen that could take advantage of apoptotic cells as a scaffold for epitope spread, and 2) an immune activator that would generate a strong and persistent T cell response to the inciting immunogen. We show that immunization of C57BL/6 and BALB/c mice with human beta(2)-glycoprotein I, an apoptotic cell-binding protein, in the presence of LPS induces a long-lived, potent response to beta(2)-glycoprotein I that results in epitope spread to multiple SLE autoantigens. SLE-specific autoantibodies emerged in a sequential manner that recapitulated the order seen in human SLE. Moreover, immunized mice developed overt glomerulonephritis closely resembling human lupus nephritis.
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Affiliation(s)
- Jerrold S. Levine
- Section of Nephrology, Department of Medicine, The University of Illinois, Chicago, IL 60612
| | - Rebecca Subang
- Division of Rheumatology, Department of Medicine, The Research Institute of the McGill University Health Centre, McGill University, Montreal, Quebec, Canada
| | - Samih H. Nasr
- Department of Pathology, Jewish General Hospital, McGill University, Montreal, Quebec, Canada
| | - Sylvie Fournier
- Department of Microbiology and Immunology, McGill University, Montreal, Quebec, Canada
| | - Ginette Lajoie
- Department of Pathology, Peel Memorial Hospital, William Osler Health Centre, Brampton, Ontario, and Department of Pathology and Laboratory Medicine, Mount Sinai Hospital, Toronto, Ontario
| | - Joan Wither
- Department of Medicine and Department of Immunology, Toronto Western Hospital Research Institute, University Health Network, University of Toronto, Toronto, Ontario, Canada
| | - Joyce Rauch
- Division of Rheumatology, Department of Medicine, The Research Institute of the McGill University Health Centre, McGill University, Montreal, Quebec, Canada
- Address correspondence and reprint requests to Dr. Joyce Rauch, The Montreal General Hospital, 1650 Cedar Avenue, Montreal, Quebec H3G 1A4, Canada.
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Yan J, Harvey BP, Gee RJ, Shlomchik MJ, Mamula MJ. B cells drive early T cell autoimmunity in vivo prior to dendritic cell-mediated autoantigen presentation. THE JOURNAL OF IMMUNOLOGY 2006; 177:4481-7. [PMID: 16982884 DOI: 10.4049/jimmunol.177.7.4481] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Both B cells and dendritic cells (DCs) have been implicated as autoantigen-presenting cells in the activation of self-reactive T cells. However, most self-proteins are ubiquitously and/or developmentally expressed, making it difficult to determine the source and the exposure of autoantigens to APCs in a controlled manner. In this study, we have used an Ig transgenic mouse model to examine the mechanisms by which B cells and other APCs acquire and present lupus autoantigens in vivo. Targeting a lupus autoantigen, the small nuclear ribonucleoprotein particle D protein, to the BCR activates autoreactive T cells in the periphery. Our in vivo studies demonstrate that autoantigen-specific B cells, when present in the repertoire, are the first subset of APCs to capture and present self-proteins for activating T cells. Thereafter, DCs acquire self-Ag and become effective APCs for stimulating the same subsets of autoreactive T cells. This mechanism provides one explanation of how early steps in autoimmunity can focus responses, via BCR, at a small group of self-proteins among the total milieu of intracellular self-proteins. Subsequently, DCs and other professional APCs may then amplify and perpetuate the autoimmune T cell response.
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Affiliation(s)
- Jun Yan
- Section of Rheumatology, Department of Internal Medicine, Yale University School of Medicine, 300 Cedar Street, New Haven, CT 06520-8031, USA
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Shimizu I, Kawahara T, Haspot F, Bardwell PD, Carroll MC, Sykes M. B-cell extrinsic CR1/CR2 promotes natural antibody production and tolerance induction of anti-alphaGAL-producing B-1 cells. Blood 2006; 109:1773-81. [PMID: 17023586 PMCID: PMC1794072 DOI: 10.1182/blood-2006-02-002386] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
B-1b cells produce IgM natural antibodies against alpha1-3Galbeta1-4GlcNAc (alphaGal). These can be tolerized by nonmyeloablative induction of mixed chimerism using alphaGal-positive (alphaGal+) donor marrow. We assessed the role of CR1/2 in this model for induction of tolerance of B-1b cells. Mixed hematopoietic chimerism was induced in alpha1-3galactosyltransferase (GalT-/-) and GalT-/-Cr2-/- mice with alphaGal+ BALB/c marrow donors. Anti-alphaGal Ab and anti-alphaGal Ab-producing B cells became undetectable in GalT-/- chimeras, whereas they persisted in chimeric GalT-/-Cr2-/- mice. To determine whether CR1/2 expression on stromal cells and/or hematopoietic cells was critical for B-1-cell tolerance, we generated GalT-/- radiation chimeras in which CR1/CR2 was expressed on either stromal cells, hematopoietic cells, neither, or both. After induction of mixed chimerism from alphaGal+ allogeneic bone marrow (BM) donors, anti-alphaGal-producing B cells were rendered tolerant in reconstituted recipients expressing only stromal CR1/CR2. Our results suggest a possible role for follicular dendritic cells that pick up immune complexes via CR1/CR2 receptors in the tolerization of B-1b cells.
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Affiliation(s)
- Ichiro Shimizu
- Bone Marrow Transplantation Section, Transplantation Biology Research Center, Massachusetts General Hospital, Harvard Medical School, Boston, USA
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48
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Qian Y, Conway KL, Lu X, Seitz HM, Matsushima GK, Clarke SH. Autoreactive MZ and B-1 B-cell activation by Faslpr is coincident with an increased frequency of apoptotic lymphocytes and a defect in macrophage clearance. Blood 2006; 108:974-82. [PMID: 16861350 PMCID: PMC1895857 DOI: 10.1182/blood-2005-12-006858] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Murine autoreactive anti-Smith (Sm) B cells are negatively regulated by anergy and developmental arrest, but are also positively selected into the marginal zone (MZ) and B-1 B-cell populations. Despite positive selection, anti-Sm production occurs only in autoimmune-prone mice. To investigate autoreactive B-cell activation, an anti-Sm transgene was combined with the lpr mutation, a mutation of the proapoptotic gene Fas (Fas(lpr)), on both autoimmune (MRL) and nonautoimmune backgrounds. Fas(lpr) induces a progressive and autoantigen-specific loss of anti-Sm MZ and B-1 B cells in young adult Fas(lpr) and MRL/Fas(lpr) mice that does not require that Fas(lpr) be B-cell intrinsic. This loss is accompanied by a bypass of the early pre-plasma cell (PC) tolerance checkpoint. Although the MRL bkg does not lead to a progressive loss of anti-Sm MZ or B-1 B cells, it induces a robust bypass of the early pre-PC tolerance checkpoint. Fas(lpr) mice have a high frequency of apoptotic lymphocytes in secondary lymphoid tissues and a macrophage defect in apoptotic cell phagocytosis. Since Sm is exposed on the surface of apoptotic cells, we propose that anti-Sm MZ and B-1 B-cell activation is the result of a Fas(lpr)-induced defect in apoptotic cell clearance.
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Affiliation(s)
- Ye Qian
- Department of Microbiology and Immunology, University of North Carolina, Chapel Hill, 27599, USA
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Wang H, Nicholas MW, Conway KL, Sen P, Diz R, Tisch RM, Clarke SH. EBV latent membrane protein 2A induces autoreactive B cell activation and TLR hypersensitivity. THE JOURNAL OF IMMUNOLOGY 2006; 177:2793-802. [PMID: 16920914 DOI: 10.4049/jimmunol.177.5.2793] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
EBV is associated with systemic lupus erythematosus (SLE), but how it might contribute to the etiology is not clear. Since EBV-encoded latent membrane protein 2A (LMP2A) interferes with normal B cell differentiation and function, we sought to determine its effect on B cell tolerance. Mice transgenic for both LMP2A and the Ig transgene 2-12H specific for the ribonucleoprotein Smith (Sm), a target of the immune system in SLE, develop a spontaneous anti-Sm response. LMP2A allows anti-Sm B cells to overcome the regulatory checkpoint at the early preplasma cell stage by a self-Ag-dependent mechanism. LMP2A induces a heightened sensitivity to TLR ligand stimulation, resulting in increased proliferation or Ab-secreting cell differentiation or both. Thus, we propose a model whereby LMP2A induces hypersensitivity to TLR stimulation, leading to activation of anti-Sm B cells through the BCR/TLR pathway. These data further implicate TLRs in the etiology of SLE and suggest a mechanistic link between EBV infection and SLE.
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Affiliation(s)
- Hongsheng Wang
- Department of Microbiology and Immunology, University of North Carolina, Chapel Hill, NC 27599, USA
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50
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Wang H, Clarke SH. Association of the pre-B cell receptor (BCR) expression level with the quality of pre-BII cell differentiation reveals hierarchical pre-BCR function. Mol Immunol 2006; 44:1765-74. [PMID: 17007932 DOI: 10.1016/j.molimm.2006.07.301] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2006] [Revised: 07/14/2006] [Accepted: 07/19/2006] [Indexed: 11/26/2022]
Abstract
The expression of a pre-B cell receptor (pre-BCR) is required for allelic exclusion and pre-BII cell differentiation. V(H)12 microH chains are unusual in that they form pre-BCRs and mediate allelic exclusion, but most cannot drive pre-BII cell differentiation. To explain this paradox, we examined pre-BCR functions and pre-BII cell differentiation in mice expressing microH chain transgenes encoding a B cell-permissible V(H)12 microH chain (designated 10/G4(6-1)), and a non-permissible V(H)12 microH chain (designated 8/G0). Compared with 10/G4 pre-BCRs, 8/G0 pre-BCRs are expressed at low levels on the cell surface. 8/G0 pre-BCRs mediate allelic exclusion, but 8/G0 pre-BII cells are defective in proliferation and expression of survival factors Bcl-2, Bcl-X(L) and hemokinin 1 (HK1). Increasing 8/G0 microH chain production restores HK1 transcription and improves proliferation of pre-BII cells as well as later stage B cell development. These data reveal a hierarchy of pre-BCR function that determines the development and plasticity of early B cells.
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Affiliation(s)
- Hongsheng Wang
- Laboratory of Immunopathology, National Institute of Allergy and Infectious Disease, National Institutes of Health, 5640 Fishers Lane, Rockville, MD 20852, USA
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