1
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Pelissier A, Stratigopoulou M, Donner N, Dimitriadis E, Bende RJ, Guikema JE, Rodriguez Martinez M, van Noesel CJ. Convergent evolution and B-cell recirculation in germinal centers in a human lymph node. Life Sci Alliance 2023; 6:e202301959. [PMID: 37640448 PMCID: PMC10462906 DOI: 10.26508/lsa.202301959] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 07/31/2023] [Accepted: 08/02/2023] [Indexed: 08/31/2023] Open
Abstract
Germinal centers (GCs) play a central role in generating an effective immune response against infectious pathogens, and failures in their regulating mechanisms can lead to the development of autoimmune diseases and cancer. Although previous works study experimental systems of the immune response with mouse models that are immunized with specific antigens, our study focused on a real-life situation, with an ongoing GC response in a human lymph node (LN) involving multiple asynchronized GCs reacting simultaneously to unknown antigens. We combined laser capture microdissection of individual GCs from human LN with next-generation repertoire sequencing to characterize individual GCs as distinct evolutionary spaces. In line with well-characterized GC responses in mice, elicited by immunization with model antigens, we observe a heterogeneous clonal diversity across individual GCs from the same human LN. Still, we identify shared clones in several individual GCs, and phylogenetic tree analysis combined with paratope modeling suggest the re-engagement and rediversification of B-cell clones across GCs and expanded clones exhibiting shared antigen responses across distinct GCs, indicating convergent evolution of the GCs.
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Affiliation(s)
- Aurelien Pelissier
- https://ror.org/02js37d36 IBM Research Europe, Rüschlikon, Switzerland
- Department of Biosystems Science and Engineering, ETH Zurich, Basel, Switzerland
| | - Maria Stratigopoulou
- Department of Pathology, Amsterdam University Medical Centers, Location AMC, Lymphoma and Myeloma Center Amsterdam, Amsterdam, Netherlands
| | - Naomi Donner
- Department of Pathology, Amsterdam University Medical Centers, Location AMC, Lymphoma and Myeloma Center Amsterdam, Amsterdam, Netherlands
| | | | - Richard J Bende
- Department of Pathology, Amsterdam University Medical Centers, Location AMC, Lymphoma and Myeloma Center Amsterdam, Amsterdam, Netherlands
| | - Jeroen E Guikema
- Department of Pathology, Amsterdam University Medical Centers, Location AMC, Lymphoma and Myeloma Center Amsterdam, Amsterdam, Netherlands
| | | | - Carel Jm van Noesel
- Department of Pathology, Amsterdam University Medical Centers, Location AMC, Lymphoma and Myeloma Center Amsterdam, Amsterdam, Netherlands
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2
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Schemel CM, Wurzel P, Scharf S, Schäfer H, Hartmann S, Koch I, Hansmann ML. Three-dimensional human germinal centers of different sizes in patients diagnosed with lymphadenitis show comparative constant relative volumes of B cells, T cells, follicular dendritic cells, and macrophages. Acta Histochem 2023; 125:152075. [PMID: 37459798 DOI: 10.1016/j.acthis.2023.152075] [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: 01/21/2023] [Revised: 06/28/2023] [Accepted: 07/05/2023] [Indexed: 10/14/2023]
Abstract
Germinal centers (GCs) are some of the most important structures in the human immune system. As such, their cell types and functions have been thoroughly investigated. B cells, T cells, follicular dendritic cells (FDCs), and macrophages have widely been found to typically be aggregated in GCs. However, the amount of space occupied by each of these cell types has yet to be investigated. In this study, we conducted confocal laser-based 3D cell-volume quantification of typical GC cells under reactive conditions in lymphadenitis and investigated how volume proportions change during GC development. For this investigation, we used anti-CD3 (T cells), anti-CD20 and anti-Pax5 (B cells), anti-CD23 (FDCs), anti-CD68 (macrophages), and DAPI (nuclear staining). We detected average proportions of about 11% CD3, 9% CD20, 6% CD23, and 2% CD68 in the largest possible regions of interest within GCs. Interestingly, these values remained steady relatively independent of GC size. The remarkably low B cell proportion can be attributed to technical constraints given the use of the CD20 antibody in 3D. Applying the B cell marker Pax5, we found that about 44% of the volume was occupied by B cells after extrapolating the volume of B cell nuclei to that of whole B cells. We concluded that Pax5 is more suitable than anti-CD20 for 3D B cell quantification in GCs. The substantial unstained volume in GCs raises the question of whether other cell types fill these open spaces. Our 3D investigation enabled a unique morphological and volumetric evaluation of GC cells that balance their overall volumes in GCs.
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Affiliation(s)
- Constantin Maximilian Schemel
- Institute of General Pharmacology and Toxicology, Goethe University Frankfurt/Main, Frankfurt/Main, Hessen, Germany.
| | - Patrick Wurzel
- Institute of General Pharmacology and Toxicology, Goethe University Frankfurt/Main, Frankfurt/Main, Hessen, Germany; Department of Molecular Bioinformatics, Institute of Computer Science, Goethe University Frankfurt/Main, Frankfurt/Main, Hessen, Germany; Frankfurt Institute for Advanced Studies (FIAS), Goethe University Frankfurt/Main, Frankfurt/Main, Hessen, Germany.
| | - Sonja Scharf
- Institute of General Pharmacology and Toxicology, Goethe University Frankfurt/Main, Frankfurt/Main, Hessen, Germany; Department of Molecular Bioinformatics, Institute of Computer Science, Goethe University Frankfurt/Main, Frankfurt/Main, Hessen, Germany; Frankfurt Institute for Advanced Studies (FIAS), Goethe University Frankfurt/Main, Frankfurt/Main, Hessen, Germany.
| | - Hendrik Schäfer
- Institute of General Pharmacology and Toxicology, Goethe University Frankfurt/Main, Frankfurt/Main, Hessen, Germany; Hospital of the Goethe University Frankfurt, Theodor-Stern-Kai 7, 60590 Frankfurt/Main, Germany.
| | - Sylvia Hartmann
- Dr. Senckenberg Institute of Pathology, Goethe University Frankfurt/Main, Frankfurt/Main, Hessen, Germany.
| | - Ina Koch
- Department of Molecular Bioinformatics, Institute of Computer Science, Goethe University Frankfurt/Main, Frankfurt/Main, Hessen, Germany.
| | - Martin-Leo Hansmann
- Institute of General Pharmacology and Toxicology, Goethe University Frankfurt/Main, Frankfurt/Main, Hessen, Germany; Frankfurt Institute for Advanced Studies (FIAS), Goethe University Frankfurt/Main, Frankfurt/Main, Hessen, Germany.
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3
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Gurwicz N, Stoler-Barak L, Schwan N, Bandyopadhyay A, Meyer-Hermann M, Shulman Z. Tingible body macrophages arise from lymph node-resident precursors and uptake B cells by dendrites. J Exp Med 2023; 220:213834. [PMID: 36705667 PMCID: PMC9900388 DOI: 10.1084/jem.20222173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Revised: 01/10/2023] [Accepted: 01/11/2023] [Indexed: 01/28/2023] Open
Abstract
Antibody affinity maturation depends on the formation of germinal centers (GCs) in lymph nodes. This process generates a massive number of apoptotic B cells, which are removed by a specialized subset of phagocytes, known as tingible body macrophages (TBMs). Although defects in these cells are associated with pathological conditions, the identity of their precursors and the dynamics of dying GC B cell disposal remained unknown. Here, we demonstrate that TBMs originate from pre-existing lymph node-resident precursors that enter the lymph node follicles in a GC-dependent manner. Intravital imaging shows that TBMs are stationary cells that selectively phagocytose GC B cells via highly dynamic protrusions and accommodate the final stages of B cell apoptosis. Cell-specific depletion and chimeric mouse models revealed that GC B cells drive TBM formation from bone marrow-derived precursors stationed within lymphoid organs prior to the immune challenge. Understanding TBM dynamics and function may explain the emergence of various antibody-mediated autoimmune conditions.
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Affiliation(s)
- Neta Gurwicz
- Department of Systems Immunology, Weizmann Institute of Science , Rehovot, Israel
| | - Liat Stoler-Barak
- Department of Systems Immunology, Weizmann Institute of Science , Rehovot, Israel
| | - Niklas Schwan
- Department of Systems Immunology and Braunschweig Integrated Centre of Systems Biology, Helmholtz Centre for Infection Research , Braunschweig, Germany
| | - Arnab Bandyopadhyay
- Department of Systems Immunology and Braunschweig Integrated Centre of Systems Biology, Helmholtz Centre for Infection Research , Braunschweig, Germany
| | - Michael Meyer-Hermann
- Department of Systems Immunology and Braunschweig Integrated Centre of Systems Biology, Helmholtz Centre for Infection Research , Braunschweig, Germany.,Institute for Biochemistry, Biotechnology and Bioinformatics, Technische Universität Braunschweig , Braunschweig, Germany
| | - Ziv Shulman
- Department of Systems Immunology, Weizmann Institute of Science , Rehovot, Israel
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4
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García-Valiente R, Merino Tejero E, Stratigopoulou M, Balashova D, Jongejan A, Lashgari D, Pélissier A, Caniels TG, Claireaux MAF, Musters A, van Gils MJ, Rodríguez Martínez M, de Vries N, Meyer-Hermann M, Guikema JEJ, Hoefsloot H, van Kampen AHC. Understanding repertoire sequencing data through a multiscale computational model of the germinal center. NPJ Syst Biol Appl 2023; 9:8. [PMID: 36927990 PMCID: PMC10019394 DOI: 10.1038/s41540-023-00271-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Accepted: 02/20/2023] [Indexed: 03/18/2023] Open
Abstract
Sequencing of B-cell and T-cell immune receptor repertoires helps us to understand the adaptive immune response, although it only provides information about the clonotypes (lineages) and their frequencies and not about, for example, their affinity or antigen (Ag) specificity. To further characterize the identified clones, usually with special attention to the particularly abundant ones (dominant), additional time-consuming or expensive experiments are generally required. Here, we present an extension of a multiscale model of the germinal center (GC) that we previously developed to gain more insight in B-cell repertoires. We compare the extent that these simulated repertoires deviate from experimental repertoires established from single GCs, blood, or tissue. Our simulations show that there is a limited correlation between clonal abundance and affinity and that there is large affinity variability among same-ancestor (same-clone) subclones. Our simulations suggest that low-abundance clones and subclones, might also be of interest since they may have high affinity for the Ag. We show that the fraction of plasma cells (PCs) with high B-cell receptor (BcR) mRNA content in the GC does not significantly affect the number of dominant clones derived from single GCs by sequencing BcR mRNAs. Results from these simulations guide data interpretation and the design of follow-up experiments.
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Affiliation(s)
- Rodrigo García-Valiente
- Amsterdam UMC location University of Amsterdam, Epidemiology and Data Science, Meibergdreef 9, Amsterdam, The Netherlands
- Amsterdam Public Health, Methodology, Amsterdam, The Netherlands
- Amsterdam Infection and Immunity, Inflammatory Diseases, Amsterdam, The Netherlands
| | - Elena Merino Tejero
- Amsterdam UMC location University of Amsterdam, Epidemiology and Data Science, Meibergdreef 9, Amsterdam, The Netherlands
- Amsterdam Public Health, Methodology, Amsterdam, The Netherlands
- Amsterdam Infection and Immunity, Inflammatory Diseases, Amsterdam, The Netherlands
| | - Maria Stratigopoulou
- Cancer Center Amsterdam, Amsterdam, The Netherlands
- Amsterdam UMC location University of Amsterdam, Medical Microbiology and Infection Prevention, Meibergdreef 9, Amsterdam, The Netherlands
| | - Daria Balashova
- Amsterdam UMC location University of Amsterdam, Epidemiology and Data Science, Meibergdreef 9, Amsterdam, The Netherlands
- Amsterdam Public Health, Methodology, Amsterdam, The Netherlands
- Amsterdam Infection and Immunity, Inflammatory Diseases, Amsterdam, The Netherlands
| | - Aldo Jongejan
- Amsterdam UMC location University of Amsterdam, Epidemiology and Data Science, Meibergdreef 9, Amsterdam, The Netherlands
- Amsterdam Public Health, Methodology, Amsterdam, The Netherlands
- Amsterdam Infection and Immunity, Inflammatory Diseases, Amsterdam, The Netherlands
| | - Danial Lashgari
- Amsterdam UMC location University of Amsterdam, Epidemiology and Data Science, Meibergdreef 9, Amsterdam, The Netherlands
- Amsterdam Public Health, Methodology, Amsterdam, The Netherlands
- Amsterdam Infection and Immunity, Inflammatory Diseases, Amsterdam, The Netherlands
| | - Aurélien Pélissier
- IBM Research Zurich, 8803, Rüschlikon, Switzerland
- Department of Biosystems Science and Engineering, ETH Zurich, 4058, Basel, Switzerland
| | - Tom G Caniels
- Amsterdam UMC location University of Amsterdam, Medical Microbiology and Infection Prevention, Meibergdreef 9, Amsterdam, The Netherlands
- Amsterdam Infection and Immunity, Infectious Diseases, Amsterdam, The Netherlands
| | - Mathieu A F Claireaux
- Amsterdam UMC location University of Amsterdam, Medical Microbiology and Infection Prevention, Meibergdreef 9, Amsterdam, The Netherlands
- Amsterdam Infection and Immunity, Infectious Diseases, Amsterdam, The Netherlands
| | - Anne Musters
- Amsterdam UMC location University of Amsterdam, Experimental Immunology, Meibergdreef 9, Amsterdam, The Netherlands
- Amsterdam Rheumatology & Immunology Center, Amsterdam, The Netherlands
| | - Marit J van Gils
- Amsterdam UMC location University of Amsterdam, Medical Microbiology and Infection Prevention, Meibergdreef 9, Amsterdam, The Netherlands
- Amsterdam Infection and Immunity, Infectious Diseases, Amsterdam, The Netherlands
| | | | - Niek de Vries
- Amsterdam UMC location University of Amsterdam, Experimental Immunology, Meibergdreef 9, Amsterdam, The Netherlands
- Amsterdam Rheumatology & Immunology Center, Amsterdam, The Netherlands
| | - Michael Meyer-Hermann
- Department for Systems Immunology and Braunschweig Integrated Centre of Systems Biology, Helmholtz Centre for Infection Research, Braunschweig, Germany
- Institute for Biochemistry, Biotechnology and Bioinformatics, Technische Universität Braunschweig, Braunschweig, Germany
| | - Jeroen E J Guikema
- Cancer Center Amsterdam, Amsterdam, The Netherlands
- Amsterdam UMC location University of Amsterdam, Pathology, Lymphoma and Myeloma Center Amsterdam, Meibergdreef 9, Amsterdam, The Netherlands
| | - Huub Hoefsloot
- Biosystems Data Analysis, Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, The Netherlands
| | - Antoine H C van Kampen
- Amsterdam UMC location University of Amsterdam, Epidemiology and Data Science, Meibergdreef 9, Amsterdam, The Netherlands.
- Amsterdam Public Health, Methodology, Amsterdam, The Netherlands.
- Amsterdam Infection and Immunity, Inflammatory Diseases, Amsterdam, The Netherlands.
- Biosystems Data Analysis, Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, The Netherlands.
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5
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Lynch TJ, Ahlers BA, Swatek AM, Ievlev V, Pai AC, Brooks L, Tang Y, Evans IA, Meyerholz DK, Engelhardt JF, Parekh KR. Ferret Lung Transplantation Models Differential Lymphoid Aggregate Morphology Between Restrictive and Obstructive Forms of Chronic Lung Allograft Dysfunction. Transplantation 2022; 106:1974-1989. [PMID: 35442232 PMCID: PMC9529760 DOI: 10.1097/tp.0000000000004148] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND Long-term survival after lung transplantation remains limited by chronic lung allograft dysfunction (CLAD). CLAD has 2 histologic phenotypes, namely obliterative bronchiolitis (OB) and restrictive alveolar fibroelastosis (AFE), which have distinct clinical presentations, pathologies, and outcomes. Understanding of OB versus AFE pathogenesis would improve with better animal models. METHODS We utilized a ferret orthotopic single-lung transplantation model to characterize allograft fibrosis as a histologic measure of CLAD. Native lobes and "No CLAD" allografts lacking aberrant histology were used as controls. We used morphometric analysis to evaluate the size and abundance of B-cell aggregates and tertiary lymphoid organs (TLOs) and their cell composition. Quantitative RNA expression of 47 target genes was performed simultaneously using a custom QuantiGene Plex Assay. RESULTS Ferret lung allografts develop the full spectrum of human CLAD histology including OB and AFE subtypes. While both OB and AFE allografts developed TLOs, TLO size and number were greater with AFE histology. More activated germinal center cells marked by B-cell lymphoma 6 Transcription Repressor, (B-cell lymphoma 6) expression and fewer cells expressing forkhead box P3 correlated with AFE, congruent with greater diffuse immunoglobulin, plasma cell abundance, and complement 4d staining. Furthermore, forkhead box P3 RNA induction was significant in OB allografts specifically. RNA expression changes were seen in native lobes of animals with AFE but not OB when compared with No CLAD native lobes. CONCLUSIONS The orthotopic ferret single-lung transplant model provides unique opportunities to better understand factors that dispose allografts to OB versus AFE. This will help develop potential immunomodulatory therapies and antifibrotic approaches for lung transplant patients.
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Affiliation(s)
- Thomas J. Lynch
- Department of Surgery, Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Bethany A. Ahlers
- Department of Surgery, Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Anthony M. Swatek
- Department of Surgery, Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Vitaly Ievlev
- Department of Anatomy and Cell Biology, Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Albert C. Pai
- Department of Surgery, Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Leonard Brooks
- Department of Surgery, Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Yinghua Tang
- Department of Anatomy and Cell Biology, Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Idil A. Evans
- Department of Anatomy and Cell Biology, Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - David K. Meyerholz
- Department of Pathology, Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - John F. Engelhardt
- Department of Anatomy and Cell Biology, Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Kalpaj R. Parekh
- Department of Surgery, Carver College of Medicine, University of Iowa, Iowa City, Iowa
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6
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Yan Z, Qi H, Lan Y. The role of geometric features in a germinal center. MATHEMATICAL BIOSCIENCES AND ENGINEERING : MBE 2022; 19:8304-8333. [PMID: 35801467 DOI: 10.3934/mbe.2022387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The germinal center (GC) is a self-organizing structure produced in the lymphoid follicle during the T-dependent immune response and is an important component of the humoral immune system. However, the impact of the special structure of GC on antibody production is not clear. According to the latest biological experiments, we establish a spatiotemporal stochastic model to simulate the whole self-organization process of the GC including the appearance of two specific zones: the dark zone (DZ) and the light zone (LZ), the development of which serves to maintain an effective competition among different cells and promote affinity maturation. A phase transition is discovered in this process, which determines the critical GC volume for a successful growth in both the stochastic and the deterministic model. Further increase of the volume does not make much improvement on the performance. It is found that the critical volume is determined by the distance between the activated B cell receptor (BCR) and the target epitope of the antigen in the shape space. The observation is confirmed in both 2D and 3D simulations and explains partly the variability of the observed GC size.
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Affiliation(s)
- Zishuo Yan
- School of Science, Beijing University of Posts and Telecommunications, Beijing 100876, China
| | - Hai Qi
- Beijing Key Lab for Immunological Research on Chronic Diseases, Tsinghua University, Beijing 100084, China
| | - Yueheng Lan
- School of Science, Beijing University of Posts and Telecommunications, Beijing 100876, China
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7
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Unveiling the Role of the Tumor Microenvironment in the Treatment of Follicular Lymphoma. Cancers (Basel) 2022; 14:cancers14092158. [PMID: 35565286 PMCID: PMC9102342 DOI: 10.3390/cancers14092158] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Revised: 04/18/2022] [Accepted: 04/21/2022] [Indexed: 12/10/2022] Open
Abstract
Simple Summary Follicular lymphoma is the most common type of indolent non-Hodgkin lymphoma and is characterized by its heterogeneity and variable course. In addition to tumor cells, the immune microenvironment plays a fundamental role in the pathogenesis of the disease. Despite advances in treatment, responses vary among patients, and outcomes are often unpredictable: a subset of high-risk patients will be refractory to standard treatments or will develop a high-grade histology. In this review, we try to understand the crosstalk between follicular lymphoma B-cells and the tumor microenvironment as well as its impact on prognosis and the risk of transformation. We also highlight recent findings related to novel therapies developed to treat this complex disease, in which genetic mutations and microenvironment cells play a key role. Abstract Follicular lymphomas (FL) are neoplasms that resemble normal germinal center (GC) B-cells. Normal GC and neoplastic follicles contain non-neoplastic cells such as T-cells, follicular dendritic cells, cancer associated fibroblasts, and macrophages, which define the tumor microenvironment (TME), which itself is an essential factor in tumor cell survival. The main characteristics of the TME in FL are an increased number of follicular regulatory T-cells (Treg) and follicular helper T-cells (Tfh), M2-polarization of macrophages, and the development of a nodular network by stromal cells that creates a suitable niche for tumor growth. All of them play important roles in tumor angiogenesis, inhibition of apoptosis, and immune evasion, which are key factors in tumor progression and transformation risk. Based on these findings, novel therapies have been developed to target specific mutations present in the TME cells, restore immune suppression, and modulate TME.
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8
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Ovchinnikov V, Karplus M. A Coarse-Grained Model of Affinity Maturation Indicates the Importance of B-Cell Receptor Avidity in Epitope Subdominance. Front Immunol 2022; 13:816634. [PMID: 35371013 PMCID: PMC8971376 DOI: 10.3389/fimmu.2022.816634] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Accepted: 01/24/2022] [Indexed: 12/02/2022] Open
Abstract
The elicitation of broadly neutralizing antibodies (bnAbs) is a major goal in the design of vaccines against rapidly-mutating viruses. In the case of influenza, many bnAbs that target conserved epitopes on the stem of the hemagglutinin protein (HA) have been discovered. However, these antibodies are rare, are not boosted well upon reinfection, and often have low neutralization potency, compared to strain-specific antibodies directed to the HA head. Different hypotheses have been proposed to explain this phenomenon. We use a coarse-grained computational model of the germinal center reaction to investigate how B-cell receptor binding valency affects the growth and affinity maturation of competing B-cells. We find that receptors that are unable to bind antigen bivalently, and also those that do not bind antigen cooperatively, have significantly slower rates of growth, memory B-cell production, and, under certain conditions, rates of affinity maturation. The corresponding B-cells are predicted to be outcompeted by B-cells that bind bivalently and cooperatively. We use the model to explore strategies for a universal influenza vaccine, e.g., how to boost the concentrations of the slower growing cross-reactive antibodies directed to the stem. The results suggest that, upon natural reinfections subsequent to vaccination, the protectiveness of such vaccines would erode, possibly requiring regular boosts. Collectively, our results strongly support the importance of bivalent antibody binding in immunodominance, and suggest guidelines for developing a universal influenza vaccine.
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Affiliation(s)
- Victor Ovchinnikov
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, United States
- *Correspondence: Victor Ovchinnikov, ; ; Martin Karplus,
| | - Martin Karplus
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, United States
- Laboratoire de Chimie Biophysique, ISIS, Université de Strasbourg, Strasbourg, France
- *Correspondence: Victor Ovchinnikov, ; ; Martin Karplus,
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9
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Yeh CH, Finney J, Okada T, Kurosaki T, Kelsoe G. Primary germinal center-resident T follicular helper cells are a physiologically distinct subset of CXCR5 hiPD-1 hi T follicular helper cells. Immunity 2022; 55:272-289.e7. [PMID: 35081372 PMCID: PMC8842852 DOI: 10.1016/j.immuni.2021.12.015] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Revised: 09/10/2021] [Accepted: 12/21/2021] [Indexed: 12/15/2022]
Abstract
T follicular helper (Tfh) cells are defined by a Bcl6+CXCR5hiPD-1hi phenotype, but only a minor fraction of these reside in germinal centers (GCs). Here, we examined whether GC-resident and -nonresident Tfh cells share a common physiology and function. Fluorescently labeled, GC-resident Tfh cells in different mouse models were distinguished by low expression of CD90. CD90neg/lo GCTfh cells required antigen-specific, MHCII+ B cells to develop and stopped proliferating soon after differentiation. In contrast, nonresident, CD90hi Tfh (GCTfh-like) cells developed normally in the absence of MHCII+ B cells and proliferated continuously during primary responses. The TCR repertoires of both Tfh subsets overlapped initially but later diverged in association with dendritic cell-dependent proliferation of CD90hi GCTfh-like cells, suggestive of TCR-dependency seen also in TCR-transgenic adoptive transfer experiments. Furthermore, the transcriptomes of CD90neg/lo and CD90hi GCTfh-like cells were enriched in different functional pathways. Thus, GC-resident and nonresident Tfh cells have distinct developmental requirements and activities, implying distinct functions.
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Affiliation(s)
- Chen-Hao Yeh
- Department of Immunology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Joel Finney
- Department of Immunology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Takaharu Okada
- Laboratory for Tissue Dynamics, RIKEN Center for Integrative Medical Sciences (IMS), Yokohama, Kanagawa 230-0045, Japan; Graduate School of Medical Life Science, Yokohama City University, Yokohama, Kanagawa 230-0045, Japan
| | - Tomohiro Kurosaki
- Laboratory of Lymphocyte Differentiation, WPI Immunology Frontier Research Center, Osaka University, Osaka 565-0871, Japan; Laboratory for Lymphocyte Differentiation, RIKEN Center for Integrative Medical Sciences (IMS), Yokohama, Kanagawa 230-0045, Japan
| | - Garnett Kelsoe
- Department of Immunology, Duke University School of Medicine, Durham, NC 27710, USA; Department of Surgery and Duke University Human Vaccine Institute, Duke University School of Medicine, Durham, NC 27710, USA.
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10
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Pae J, Jacobsen JT, Victora GD. Imaging the different timescales of germinal center selection. Immunol Rev 2021; 306:234-243. [PMID: 34825386 DOI: 10.1111/imr.13039] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Accepted: 11/06/2021] [Indexed: 12/16/2022]
Abstract
Germinal centers (GCs) are the site of antibody affinity maturation, a fundamental immunological process that increases the potency of antibodies and thereby their ability to protect against infection. GC biology is highly dynamic in both time and space, making it ideally suited for intravital imaging. Using multiphoton laser scanning microscopy (MPLSM), the field has gained insight into the molecular, cellular, and structural changes and movements that coordinate affinity maturation in real time in their native environment. On the other hand, several limitations of MPLSM have had to be overcome to allow full appreciation of GC events taking place across different timescales. Here, we review the technical advances afforded by intravital imaging and their contributions to our understanding of GC biology.
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Affiliation(s)
- Juhee Pae
- Laboratory of Lymphocyte Dynamics, The Rockefeller University, New York, New York, USA
| | - Johanne T Jacobsen
- Laboratory of Lymphocyte Dynamics, The Rockefeller University, New York, New York, USA
| | - Gabriel D Victora
- Laboratory of Lymphocyte Dynamics, The Rockefeller University, New York, New York, USA
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11
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Molari M, Monasson R, Cocco S. Survival probability and size of lineages in antibody affinity maturation. Phys Rev E 2021; 103:052413. [PMID: 34134280 DOI: 10.1103/physreve.103.052413] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Accepted: 05/06/2021] [Indexed: 11/07/2022]
Abstract
Affinity maturation (AM) is the process through which the immune system is able to develop potent antibodies against new pathogens it encounters, and is at the base of the efficacy of vaccines. At its core AM is analogous to a Darwinian evolutionary process, where B cells mutate and are selected on the base of their affinity for an antigen (Ag), and Ag availability tunes the selective pressure. In cases when this selective pressure is high, the number of B cells might quickly decrease and the population might risk extinction in what is known as a population bottleneck. Here we study the probability for a B-cell lineage to survive this bottleneck scenario as a function of the progenitor affinity for the Ag. Using recursive relations and probability generating functions we derive expressions for the average extinction time and progeny size for lineages that go extinct. We then extend our results to the full population, both in the absence and presence of competition for T-cell help, and quantify the population survival probability as a function of Ag concentration and initial population size. Our study suggests the population bottleneck phenomenology might represent a limit case in the space of biologically plausible maturation scenarios, whose characterization could help guide the process of vaccine development.
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Affiliation(s)
- Marco Molari
- Laboratoire de Physique de l'École Normale Supérieure, ENS, PSL University, CNRS UMR8023, Sorbonne Université, Université de Paris, 24 rue Lhomond, 75005 Paris, France
| | - Rémi Monasson
- Laboratoire de Physique de l'École Normale Supérieure, ENS, PSL University, CNRS UMR8023, Sorbonne Université, Université de Paris, 24 rue Lhomond, 75005 Paris, France
| | - Simona Cocco
- Laboratoire de Physique de l'École Normale Supérieure, ENS, PSL University, CNRS UMR8023, Sorbonne Université, Université de Paris, 24 rue Lhomond, 75005 Paris, France
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12
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Anania JC, Westin A, Adler J, Heyman B. A Novel Image Analysis Approach Reveals a Role for Complement Receptors 1 and 2 in Follicular Dendritic Cell Organization in Germinal Centers. Front Immunol 2021; 12:655753. [PMID: 33912182 PMCID: PMC8072117 DOI: 10.3389/fimmu.2021.655753] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Accepted: 03/22/2021] [Indexed: 11/15/2022] Open
Abstract
Follicular dendritic cells (FDCs) are rare and enigmatic cells that mainly reside in germinal centers (GCs). They are capable of capturing immune complexes, via their Fc (FcRs) and complement receptors (CRs) and storing them for long periods in non-degradative vesicles. Presentation of ICs on FDCs to B cells is believed to drive affinity maturation. CR1 and CR2 are expressed on B cells and FDCs. Cr2 knock out (KO) mice, lacking both receptors, have impaired antibody and GC responses. Utilizing a novel ImageJ macro to analyze confocal fluorescence microscopy images of spleen sections, we here investigate how FDCs in wild type (WT) and Cr2 KO mice behave during the first two weeks after immunization with sheep red blood cells (SRBC). Mice were immunized with SRBC i.v. and spleen and serum samples harvested at various time points. As expected, antibody and GC responses in Cr2 KO mice were impaired in comparison to WT mice. Fewer FDCs were identified in Cr2 KO mice, and these exhibited differential localization and organization in comparison to WT mice. WT FDCs were primarily located within GCs at the light zone/dark zone border. FDCs from WT but not Cr2 KO mice were actively dispersed in GCs, i.e. tended to move away from each other, presumably to increase their surface area for B cell interaction. FDCs from Cr2 KO mice were more often found on follicles outside of the GCs and those within the GCs were closer to the periphery in comparison to WT FDCs. Expression of CR1 and CR2, FcγRIIB, and FcµR increased in FDCs from WT mice during the course of immunization. The results suggest that decreased ability to capture ICs by FDCs lacking CR1 and CR2 may not be the only explanation for the impaired GC and antibody responses in Cr2 KO mice. Poor FDC organization in GCs and failure to increase receptor expression after immunization may further contribute to the inefficient immune responses observed.
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Affiliation(s)
- Jessica C. Anania
- Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
| | - Annika Westin
- Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
| | - Jeremy Adler
- Department of Immunology, Genetics and Pathology, Facilities, BioVis, Uppsala University, Uppsala, Sweden
| | - Birgitta Heyman
- Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
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13
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Verheijen M, Rane S, Pearson C, Yates AJ, Seddon B. Fate Mapping Quantifies the Dynamics of B Cell Development and Activation throughout Life. Cell Rep 2020; 33:108376. [PMID: 33207189 PMCID: PMC8622872 DOI: 10.1016/j.celrep.2020.108376] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 07/29/2020] [Accepted: 10/21/2020] [Indexed: 01/10/2023] Open
Abstract
Follicular mature (FM) and germinal center (GC) B cells underpin humoral immunity, but the dynamics of their generation and maintenance are not clearly defined. Here, we exploited a fate-mapping system in mice that tracks B cells as they develop into peripheral subsets, together with a cell division fate reporter mouse and mathematical models. We find that FM cells are kinetically homogeneous, recirculate freely, are continually replenished from transitional populations, and self-renew rarely. In contrast, GC B cell lineages persist for weeks with rapid turnover and site-specific dynamics. Those in the spleen derive from transitional cells and are kinetically homogeneous, while those in lymph nodes derive from FM B cells and comprise both transient and persistent clones. These differences likely derive from the nature of antigen exposure at the different sites. Our integrative approach also reveals how the host environment drives cell-extrinsic, age- related changes in B cell homeostasis. Verheijen and Rane et al. combine fate mapping and mathematical models to quantify the development and dynamics of follicular mature B cells and germinal center B cells in spleen and lymph nodes, and show how these processes vary across the mouse lifespan.
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Affiliation(s)
- Melissa Verheijen
- Institute of Immunity and Transplantation, Division of Infection and Immunity, UCL, Royal Free Hospital, Rowland Hill Street, London NW3 2PF, UK
| | - Sanket Rane
- Department of Pathology and Cell Biology, Columbia University Medical Center, 701 West 168th Street, New York, NY 10032, USA
| | - Claire Pearson
- Kennedy Institute of Rheumatology, University of Oxford, Oxford, UK
| | - Andrew J Yates
- Department of Pathology and Cell Biology, Columbia University Medical Center, 701 West 168th Street, New York, NY 10032, USA.
| | - Benedict Seddon
- Institute of Immunity and Transplantation, Division of Infection and Immunity, UCL, Royal Free Hospital, Rowland Hill Street, London NW3 2PF, UK.
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14
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Molari M, Eyer K, Baudry J, Cocco S, Monasson R. Quantitative modeling of the effect of antigen dosage on B-cell affinity distributions in maturating germinal centers. eLife 2020; 9:e55678. [PMID: 32538783 PMCID: PMC7360369 DOI: 10.7554/elife.55678] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2020] [Accepted: 06/12/2020] [Indexed: 12/11/2022] Open
Abstract
Affinity maturation is a complex dynamical process allowing the immune system to generate antibodies capable of recognizing antigens. We introduce a model for the evolution of the distribution of affinities across the antibody population in germinal centers. The model is amenable to detailed mathematical analysis and gives insight on the mechanisms through which antigen availability controls the rate of maturation and the expansion of the antibody population. It is also capable, upon maximum-likelihood inference of the parameters, to reproduce accurately the distributions of affinities of IgG-secreting cells we measure in mice immunized against Tetanus Toxoid under largely varying conditions (antigen dosage, delay between injections). Both model and experiments show that the average population affinity depends non-monotonically on the antigen dosage. We show that combining quantitative modeling and statistical inference is a concrete way to investigate biological processes underlying affinity maturation (such as selection permissiveness), hardly accessible through measurements.
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Affiliation(s)
- Marco Molari
- Laboratoire de Physique de l’École Normale Supérieure, ENS, PSL University, CNRS UMR8023, Sorbonne Université, Université Paris-Diderot, Sorbonne Paris CitéParisFrance
| | - Klaus Eyer
- Laboratory for Functional Immune Repertoire Analysis, Institute of Pharmaceutical Sciences, ETH ZurichZurichSwitzerland
| | - Jean Baudry
- Laboratoire Colloides et Materiaux Divises (LCMD), Chemistry, Biology and Innovation (CBI), ESPCI, PSL Research and CNRSParisFrance
| | - Simona Cocco
- Laboratoire de Physique de l’École Normale Supérieure, ENS, PSL University, CNRS UMR8023, Sorbonne Université, Université Paris-Diderot, Sorbonne Paris CitéParisFrance
| | - Rémi Monasson
- Laboratoire de Physique de l’École Normale Supérieure, ENS, PSL University, CNRS UMR8023, Sorbonne Université, Université Paris-Diderot, Sorbonne Paris CitéParisFrance
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15
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Pélissier A, Akrout Y, Jahn K, Kuipers J, Klein U, Beerenwinkel N, Rodríguez Martínez M. Computational Model Reveals a Stochastic Mechanism behind Germinal Center Clonal Bursts. Cells 2020; 9:E1448. [PMID: 32532145 PMCID: PMC7349200 DOI: 10.3390/cells9061448] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 05/29/2020] [Accepted: 06/08/2020] [Indexed: 02/06/2023] Open
Abstract
Germinal centers (GCs) are specialized compartments within the secondary lymphoid organs where B cells proliferate, differentiate, and mutate their antibody genes in response to the presence of foreign antigens. Through the GC lifespan, interclonal competition between B cells leads to increased affinity of the B cell receptors for antigens accompanied by a loss of clonal diversity, although the mechanisms underlying clonal dynamics are not completely understood. We present here a multi-scale quantitative model of the GC reaction that integrates an intracellular component, accounting for the genetic events that shape B cell differentiation, and an extracellular stochastic component, which accounts for the random cellular interactions within the GC. In addition, B cell receptors are represented as sequences of nucleotides that mature and diversify through somatic hypermutations. We exploit extensive experimental characterizations of the GC dynamics to parameterize our model, and visualize affinity maturation by means of evolutionary phylogenetic trees. Our explicit modeling of B cell maturation enables us to characterise the evolutionary processes and competition at the heart of the GC dynamics, and explains the emergence of clonal dominance as a result of initially small stochastic advantages in the affinity to antigen. Interestingly, a subset of the GC undergoes massive expansion of higher-affinity B cell variants (clonal bursts), leading to a loss of clonal diversity at a significantly faster rate than in GCs that do not exhibit clonal dominance. Our work contributes towards an in silico vaccine design, and has implications for the better understanding of the mechanisms underlying autoimmune disease and GC-derived lymphomas.
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Affiliation(s)
- Aurélien Pélissier
- IBM Research Zurich, 8803 Rüschlikon, Switzerland
- Department of Biosystems Science and Engineering, ETH Zurich, 4058 Basel, Switzerland; (K.J.); (J.K.); (N.B.)
| | | | - Katharina Jahn
- Department of Biosystems Science and Engineering, ETH Zurich, 4058 Basel, Switzerland; (K.J.); (J.K.); (N.B.)
| | - Jack Kuipers
- Department of Biosystems Science and Engineering, ETH Zurich, 4058 Basel, Switzerland; (K.J.); (J.K.); (N.B.)
| | - Ulf Klein
- Leeds Institute of Medical Research at St. James’s, University of Leeds, Leeds LS9 7TF, UK;
| | - Niko Beerenwinkel
- Department of Biosystems Science and Engineering, ETH Zurich, 4058 Basel, Switzerland; (K.J.); (J.K.); (N.B.)
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16
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Shlomchik MJ, Luo W, Weisel F. Linking signaling and selection in the germinal center. Immunol Rev 2019; 288:49-63. [PMID: 30874353 DOI: 10.1111/imr.12744] [Citation(s) in RCA: 85] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Accepted: 01/24/2019] [Indexed: 12/24/2022]
Abstract
Germinal centers (GC) are sites of rapid B-cell proliferation in response to certain types of immunization. They arise in about 1 week and can persist for several months. In GCs, B cells differentiate in a unique way and begin to undergo somatic mutation of the Ig V regions at a high rate. GC B cells (GCBC) thus undergo clonal diversification that can affect the affinity of the newly mutant B-cell receptor (BCR) for its driving antigen. Through processes that are still poorly understood, GCBC with higher affinity are selectively expanded while those with mutations that inactivate the BCR are lost. In addition, at various times during the extended GC reaction, some GCBC undergo differentiation into either long-lived memory B cells (MBC) or plasma cells. The cellular and molecular signals that govern these fate decisions are not well-understood, but are an active area of research in multiple laboratories. In this review, we cover both the history of this field and focus on recent work that has helped to elucidate the signals and molecules, such as key transcription factors, that coordinate both positive selection as well as differentiation of GCBC.
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Affiliation(s)
- Mark J Shlomchik
- Department of Immunology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Wei Luo
- Department of Immunology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Florian Weisel
- Department of Immunology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
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17
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Stoler-Barak L, Biram A, Davidzohn N, Addadi Y, Golani O, Shulman Z. B cell dissemination patterns during the germinal center reaction revealed by whole-organ imaging. J Exp Med 2019; 216:2515-2530. [PMID: 31492809 PMCID: PMC6829594 DOI: 10.1084/jem.20190789] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Revised: 07/02/2019] [Accepted: 08/07/2019] [Indexed: 01/04/2023] Open
Abstract
Antibody-mediated long-lasting protection from harmful pathogens depends on collaboration of immune cells within immunological niches. Stoler-Barak et al. introduce an approach that enables the visualization of all the germinal center niches and activated B cells within intact lymph nodes. Germinal centers (GCs) are sites wherein B cells proliferate and mutate their immunoglobulins in the dark zone (DZ), followed by affinity-based selection in the light zone (LZ). Here, we mapped the location of single B cells in the context of intact lymph nodes (LNs) throughout the GC response, and examined the role of BCR affinity in dictating their position. Imaging of entire GC structures and proximal single cells by light-sheet fluorescence microscopy revealed that individual B cells that previously expressed AID are located within the LN cortex, in an area close to the GC LZ. Using in situ photoactivation, we demonstrated that B cells migrate from the LZ toward the GC outskirts, while DZ B cells are confined to the GC. B cells expressing very-low-affinity BCRs formed GCs but were unable to efficiently disperse within the follicles. Our findings reveal that BCR affinity regulates B cell positioning during the GC response.
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Affiliation(s)
- Liat Stoler-Barak
- Department of Immunology, Weizmann Institute of Science, Rehovot, Israel
| | - Adi Biram
- Department of Immunology, Weizmann Institute of Science, Rehovot, Israel
| | - Natalia Davidzohn
- Department of Immunology, Weizmann Institute of Science, Rehovot, Israel
| | - Yoseph Addadi
- Life Sciences Core Facilities, Weizmann Institute of Science, Rehovot, Israel
| | - Ofra Golani
- Life Sciences Core Facilities, Weizmann Institute of Science, Rehovot, Israel
| | - Ziv Shulman
- Department of Immunology, Weizmann Institute of Science, Rehovot, Israel
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18
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Faro J, von Haeften B, Gardner R, Faro E. A Sensitivity Analysis Comparison of Three Models for the Dynamics of Germinal Centers. Front Immunol 2019; 10:2038. [PMID: 31543878 PMCID: PMC6729701 DOI: 10.3389/fimmu.2019.02038] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Accepted: 08/12/2019] [Indexed: 01/25/2023] Open
Abstract
Germinal centers (GCs) are transient anatomical microenvironments where antibody affinity maturation and memory B cells generation takes place. In the past, models of Germinal Center (GC) dynamics have focused on understanding antibody affinity maturation rather than on the main mechanism(s) driving their rise-and-fall dynamics. Here, based on a population dynamics model core, we compare three mechanisms potentially responsible for this GC biphasic behavior dependent on follicular dendritic cell (FDC) maturation, follicular T helper (Tfh) cell maturation, and antigen depletion. Analyzing the kinetics of B and T cells, as well as its parameter sensitivities, we found that only the FDC-maturation-based model could describe realistic GC dynamics, whereas the simple Tfh-maturation and antigen-depletion mechanisms, as implemented here, could not. We also found that in all models the processes directly related to Tfh cell kinetics have the highest impact on GC dynamics. This suggests the existence of some still unknown mechanism(s) tuning GC dynamics by affecting Tfh cell response to proliferation-inducing stimuli.
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Affiliation(s)
- Jose Faro
- Area of Immunology, Faculty of Biology, CINBIO (Biomedical Research Center), University of Vigo, Vigo, Spain
- Instituto Biomédico de Vigo, Vigo, Spain
- Instituto Gulbenkian de Ciência, Oeiras, Portugal
| | - Bernardo von Haeften
- Departamento de Física, FCEyN, Universidad Nacional de Mar del Plata, Mar del Plata, Argentina
| | - Rui Gardner
- Instituto Gulbenkian de Ciência, Oeiras, Portugal
| | - Emilio Faro
- Department of Applied Mathematics II, University of Vigo, Vigo, Spain
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19
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Murugan R, Buchauer L, Triller G, Kreschel C, Costa G, Pidelaserra Martí G, Imkeller K, Busse CE, Chakravarty S, Sim BKL, Hoffman SL, Levashina EA, Kremsner PG, Mordmüller B, Höfer T, Wardemann H. Clonal selection drives protective memory B cell responses in controlled human malaria infection. Sci Immunol 2018; 3:3/20/eaap8029. [DOI: 10.1126/sciimmunol.aap8029] [Citation(s) in RCA: 109] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Accepted: 11/30/2017] [Indexed: 01/20/2023]
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20
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Sudres M, Verdier J, Truffault F, Le Panse R, Berrih-Aknin S. Pathophysiological mechanisms of autoimmunity. Ann N Y Acad Sci 2018; 1413:59-68. [PMID: 29377165 DOI: 10.1111/nyas.13560] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Revised: 10/29/2017] [Accepted: 10/30/2017] [Indexed: 12/12/2022]
Abstract
Autoimmune diseases (AIDs) are chronic disorders characterized by inflammatory reactions against self-antigens that can be either systemic or organ specific. AIDs can differ in their epidemiologic features and clinical presentations, yet all share a remarkable complexity. AIDs result from an interplay of genetic and epigenetic factors with environmental components that are associated with imbalances in the immune system. Many of the pathogenic mechanisms of AIDs are also implicated in myasthenia gravis (MG), an AID in which inflammation of the thymus leads to a neuromuscular disorder. Our goal here is to highlight the similarities and differences between MG and other AIDs by reviewing the common transcriptome signatures and the development of germinal centers and by discussing some unresolved questions about autoimmune mechanisms. This review will propose hypotheses to explain the origin of regulatory T (Treg ) cell defects and the causes of chronicity and specificity of AIDs.
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Affiliation(s)
- Muriel Sudres
- INSERM U974, Paris, France.,UPMC Sorbonne Universités, Paris, France.,AIM, Institut de Myologie, Paris, France
| | - Julien Verdier
- INSERM U974, Paris, France.,UPMC Sorbonne Universités, Paris, France.,AIM, Institut de Myologie, Paris, France
| | - Frédérique Truffault
- INSERM U974, Paris, France.,UPMC Sorbonne Universités, Paris, France.,AIM, Institut de Myologie, Paris, France
| | - Rozen Le Panse
- INSERM U974, Paris, France.,UPMC Sorbonne Universités, Paris, France.,AIM, Institut de Myologie, Paris, France
| | - Sonia Berrih-Aknin
- INSERM U974, Paris, France.,UPMC Sorbonne Universités, Paris, France.,AIM, Institut de Myologie, Paris, France
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21
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Reshetova P, van Schaik BDC, Klarenbeek PL, Doorenspleet ME, Esveldt REE, Tak PP, Guikema JEJ, de Vries N, van Kampen AHC. Computational Model Reveals Limited Correlation between Germinal Center B-Cell Subclone Abundancy and Affinity: Implications for Repertoire Sequencing. Front Immunol 2017; 8:221. [PMID: 28321219 PMCID: PMC5337809 DOI: 10.3389/fimmu.2017.00221] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Accepted: 02/16/2017] [Indexed: 12/18/2022] Open
Abstract
Immunoglobulin repertoire sequencing has successfully been applied to identify expanded antigen-activated B-cell clones that play a role in the pathogenesis of immune disorders. One challenge is the selection of the Ag-specific B cells from the measured repertoire for downstream analyses. A general feature of an immune response is the expansion of specific clones resulting in a set of subclones with common ancestry varying in abundance and in the number of acquired somatic mutations. The expanded subclones are expected to have BCR affinities for the Ag higher than the affinities of the naive B cells in the background population. For these reasons, several groups successfully proceeded or suggested selecting highly abundant subclones from the repertoire to obtain the Ag-specific B cells. Given the nature of affinity maturation one would expect that abundant subclones are of high affinity but since repertoire sequencing only provides information about abundancies, this can only be verified with additional experiments, which are very labor intensive. Moreover, this would also require knowledge of the Ag, which is often not available for clinical samples. Consequently, in general we do not know if the selected highly abundant subclone(s) are also the high(est) affinity subclones. Such knowledge would likely improve the selection of relevant subclones for further characterization and Ag screening. Therefore, to gain insight in the relation between subclone abundancy and affinity, we developed a computational model that simulates affinity maturation in a single GC while tracking individual subclones in terms of abundancy and affinity. We show that the model correctly captures the overall GC dynamics, and that the amount of expansion is qualitatively comparable to expansion observed from B cells isolated from human lymph nodes. Analysis of the fraction of high- and low-affinity subclones among the unexpanded and expanded subclones reveals a limited correlation between abundancy and affinity and shows that the low abundant subclones are of highest affinity. Thus, our model suggests that selecting highly abundant subclones from repertoire sequencing experiments would not always lead to the high(est) affinity B cells. Consequently, additional or alternative selection approaches need to be applied.
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Affiliation(s)
- Polina Reshetova
- Biosystems Data Analysis, Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, Netherlands; Bioinformatics Laboratory, Academic Medical Center, University of Amsterdam, Amsterdam, Netherlands
| | - Barbera D C van Schaik
- Bioinformatics Laboratory, Academic Medical Center, University of Amsterdam , Amsterdam , Netherlands
| | - Paul L Klarenbeek
- Amsterdam Rheumatology and Immunology Center, Academic Medical Center , Amsterdam , Netherlands
| | - Marieke E Doorenspleet
- Amsterdam Rheumatology and Immunology Center, Academic Medical Center , Amsterdam , Netherlands
| | - Rebecca E E Esveldt
- Amsterdam Rheumatology and Immunology Center, Academic Medical Center , Amsterdam , Netherlands
| | - Paul-Peter Tak
- Department of Clinical Immunology and Rheumatology, Academic Medical Center, University of Amsterdam , Amsterdam , Netherlands
| | - Jeroen E J Guikema
- Department of Pathology, Academic Medical Center, University of Amsterdam , Amsterdam , Netherlands
| | - Niek de Vries
- Amsterdam Rheumatology and Immunology Center, Academic Medical Center , Amsterdam , Netherlands
| | - Antoine H C van Kampen
- Biosystems Data Analysis, Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, Netherlands; Bioinformatics Laboratory, Academic Medical Center, University of Amsterdam, Amsterdam, Netherlands
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22
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Essential role of immobilized chemokine CXCL12 in the regulation of the humoral immune response. Proc Natl Acad Sci U S A 2017; 114:2319-2324. [PMID: 28193885 DOI: 10.1073/pnas.1611958114] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Chemokines control the migration of a large array of cells by binding to specific receptors on cell surfaces. The biological function of chemokines also depends on interactions between nonreceptor binding domains and proteoglycans, which mediate chemokine immobilization on cellular or extracellular surfaces and formation of fixed gradients. Chemokine gradients regulate synchronous cell motility and integrin-dependent cell adhesion. Of the various chemokines, CXCL12 has a unique structure because its receptor-binding domain is distinct and does not overlap with the immobilization domains. Although CXCL12 is known to be essential for the germinal center (GC) response, the role of its immobilization in biological functions has never been addressed. In this work, we investigated the unexplored paradigm of CXCL12 immobilization during the germinal center reaction, a fundamental process where cellular traffic is crucial for the quality of humoral immune responses. We show that the structure of murine germinal centers and the localization of GC B cells are impaired when CXCL12 is unable to bind to cellular or extracellular surfaces. In such mice, B cells carry fewer somatic mutations in Ig genes and are impaired in affinity maturation. Therefore, immobilization of CXCL12 is necessary for proper trafficking of B cells during GC reaction and for optimal humoral immune responses.
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23
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Truffault F, de Montpreville V, Eymard B, Sharshar T, Le Panse R, Berrih-Aknin S. Thymic Germinal Centers and Corticosteroids in Myasthenia Gravis: an Immunopathological Study in 1035 Cases and a Critical Review. Clin Rev Allergy Immunol 2017; 52:108-124. [PMID: 27273086 DOI: 10.1007/s12016-016-8558-3] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
The most common form of Myasthenia gravis (MG) is due to anti-acetylcholine receptor (AChR) antibodies and is frequently associated with thymic pathology. In this review, we discuss the immunopathological characteristics and molecular mechanisms of thymic follicular hyperplasia, the effects of corticosteroids on this thymic pathology, and the role of thymic epithelial cells (TEC), a key player in the inflammatory thymic mechanisms. This review is based not only on the literature data but also on thymic transcriptome results and analyses of pathological and immunological correlations in a vast cohort of 1035 MG patients without thymoma. We show that among patients presenting a thymic hyperplasia with germinal centers (GC), 80 % are females, indicating that thymic follicular hyperplasia is mainly a disease of women. The presence of anti-AChR antibodies is correlated with the degree of follicular hyperplasia, suggesting that the thymus is a source of anti-AChR antibodies. The degree of hyperplasia is not dependent upon the time from the onset, implying that either the antigen is chronically expressed and/or that the mechanisms of the resolution of the GC are not efficiently controlled. Glucocorticoids, a conventional therapy in MG, induce a significant reduction in the GC number, together with changes in the expression of chemokines and angiogenesis. These changes are likely related to the acetylation molecular process, overrepresented in corticosteroid-treated patients, and essential for gene regulation. Altogether, based on the pathological and molecular thymic abnormalities found in MG patients, this review provides some explanations for the benefit of thymectomy in early-onset MG patients.
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Affiliation(s)
- Frédérique Truffault
- INSERM U974, Paris, France.,CNRS FRE3617, Paris, France.,Sorbonne Universités, UPMC Univ Paris 06, Paris, France.,AIM, Institut de myologie, Paris, France
| | | | - Bruno Eymard
- Department of Neuromuscular Disorders, CHU Salpêtrière, Paris, France
| | - Tarek Sharshar
- General Intensive Care Medicine, Assistance Publique Hôpitaux de Paris, Raymond Poincaré Hospital, University of Versailles Saint-Quentin en Yvelines, 92380, Garches, France
| | - Rozen Le Panse
- INSERM U974, Paris, France.,CNRS FRE3617, Paris, France.,Sorbonne Universités, UPMC Univ Paris 06, Paris, France.,AIM, Institut de myologie, Paris, France
| | - Sonia Berrih-Aknin
- INSERM U974, Paris, France. .,CNRS FRE3617, Paris, France. .,Sorbonne Universités, UPMC Univ Paris 06, Paris, France. .,AIM, Institut de myologie, Paris, France. .,UMRS 974 UPMC, INSERM, FRE 3617 CNRS, AIM, Center of Research in Myology, 105 Boulevard de l'Hôpital, Paris, 75013, France.
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24
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Abbott RK, Thayer M, Labuda J, Silva M, Philbrook P, Cain DW, Kojima H, Hatfield S, Sethumadhavan S, Ohta A, Reinherz EL, Kelsoe G, Sitkovsky M. Germinal Center Hypoxia Potentiates Immunoglobulin Class Switch Recombination. THE JOURNAL OF IMMUNOLOGY 2016; 197:4014-4020. [PMID: 27798169 DOI: 10.4049/jimmunol.1601401] [Citation(s) in RCA: 81] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2016] [Accepted: 09/16/2016] [Indexed: 11/19/2022]
Abstract
Germinal centers (GCs) are anatomic sites where B cells undergo secondary diversification to produce high-affinity, class-switched Abs. We hypothesized that proliferating B cells in GCs create a hypoxic microenvironment that governs their further differentiation. Using molecular markers, we found GCs to be predominantly hypoxic. Compared to normoxia (21% O2), hypoxic culture conditions (1% O2) in vitro accelerated class switching and plasma cell formation and enhanced expression of GL-7 on B and CD4+ T cells. Reversal of GC hypoxia in vivo by breathing 60% O2 during immunization resulted in reduced frequencies of GC B cells, T follicular helper cells, and plasmacytes, as well as lower expression of ICOS on T follicular helper cells. Importantly, this reversal of GC hypoxia decreased Ag-specific serum IgG1 and reduced the frequency of IgG1+ B cells within the Ag-specific GC. Taken together, these observations reveal a critical role for hypoxia in GC B cell differentiation.
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Affiliation(s)
- Robert K Abbott
- New England Inflammation and Tissue Protection Institute, Northeastern University, Boston, MA 02115;
| | - Molly Thayer
- New England Inflammation and Tissue Protection Institute, Northeastern University, Boston, MA 02115
| | - Jasmine Labuda
- New England Inflammation and Tissue Protection Institute, Northeastern University, Boston, MA 02115
| | - Murillo Silva
- New England Inflammation and Tissue Protection Institute, Northeastern University, Boston, MA 02115
| | - Phaethon Philbrook
- New England Inflammation and Tissue Protection Institute, Northeastern University, Boston, MA 02115
| | - Derek W Cain
- Department of Immunology and Human Vaccine Institute, Duke University, Durham, NC 27710
| | - Hidefumi Kojima
- Department of Immunology, Dokkyo Medical University School of Medicine, Tochigi 321-0293, Japan; and
| | - Stephen Hatfield
- New England Inflammation and Tissue Protection Institute, Northeastern University, Boston, MA 02115
| | - Shalini Sethumadhavan
- New England Inflammation and Tissue Protection Institute, Northeastern University, Boston, MA 02115
| | - Akio Ohta
- New England Inflammation and Tissue Protection Institute, Northeastern University, Boston, MA 02115
| | - Ellis L Reinherz
- Laboratory of Immunobiology, Department of Medical Oncology, Dana Farber Cancer Institute and Harvard Medical School, Boston, MA 02115
| | - Garnett Kelsoe
- Department of Immunology and Human Vaccine Institute, Duke University, Durham, NC 27710
| | - Michail Sitkovsky
- New England Inflammation and Tissue Protection Institute, Northeastern University, Boston, MA 02115
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25
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Childs LM, Baskerville EB, Cobey S. Trade-offs in antibody repertoires to complex antigens. Philos Trans R Soc Lond B Biol Sci 2016; 370:rstb.2014.0245. [PMID: 26194759 PMCID: PMC4528422 DOI: 10.1098/rstb.2014.0245] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Pathogens vary in their antigenic complexity. While some pathogens such as measles present a few relatively invariant targets to the immune system, others such as malaria display considerable antigenic diversity. How the immune response copes in the presence of multiple antigens, and whether a trade-off exists between the breadth and efficacy of antibody (Ab)-mediated immune responses, are unsolved problems. We present a theoretical model of affinity maturation of B-cell receptors (BCRs) during a primary infection and examine how variation in the number of accessible antigenic sites alters the Ab repertoire. Naive B cells with randomly generated receptor sequences initiate the germinal centre (GC) reaction. The binding affinity of a BCR to an antigen is quantified via a genotype-phenotype map, based on a random energy landscape, that combines local and distant interactions between residues. In the presence of numerous antigens or epitopes, B-cell clones with different specificities compete for stimulation during rounds of mutation within GCs. We find that the availability of many epitopes reduces the affinity and relative breadth of the Ab repertoire. Despite the stochasticity of somatic hypermutation, patterns of immunodominance are strongly shaped by chance selection of naive B cells with specificities for particular epitopes. Our model provides a mechanistic basis for the diversity of Ab repertoires and the evolutionary advantage of antigenically complex pathogens.
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Affiliation(s)
- Lauren M Childs
- Center for Communicable Disease Dynamics, Harvard T.H. Chan School of Public Health, Boston, MA, USA Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | | | - Sarah Cobey
- Ecology and Evolution, University of Chicago, Chicago, IL, USA
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26
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Cobey S, Wilson P, Matsen FA. The evolution within us. Philos Trans R Soc Lond B Biol Sci 2015; 370:20140235. [PMID: 26194749 PMCID: PMC4528412 DOI: 10.1098/rstb.2014.0235] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/18/2015] [Indexed: 01/05/2023] Open
Abstract
The B-cell immune response is a remarkable evolutionary system found in jawed vertebrates. B-cell receptors, the membrane-bound form of antibodies, are capable of evolving high affinity to almost any foreign protein. High germline diversity and rapid evolution upon encounter with antigen explain the general adaptability of B-cell populations, but the dynamics of repertoires are less well understood. These dynamics are scientifically and clinically important. After highlighting the remarkable characteristics of naive and experienced B-cell repertoires, especially biased usage of genes encoding the B-cell receptors, we contrast methods of sequence analysis and their attempts to explain patterns of B-cell evolution. These phylogenetic approaches are currently unlinked to explicit models of B-cell competition, which analyse repertoire evolution at the level of phenotype, the affinities and specificities to particular antigenic sites. The models, in turn, suggest how chance, infection history and other factors contribute to different patterns of immunodominance and protection between people. Challenges in rational vaccine design, specifically vaccines to induce broadly neutralizing antibodies to HIV, underscore critical gaps in our understanding of B cells' evolutionary and ecological dynamics.
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Affiliation(s)
- Sarah Cobey
- Department of Ecology and Evolution, University of Chicago, Chicago, IL 60637, USA
| | - Patrick Wilson
- Department of Medicine, University of Chicago, Chicago, IL 60637, USA Committee on Immunology, University of Chicago, Chicago, IL 60637, USA Knapp Center for Lupus and Immunology Research, University of Chicago, Chicago, IL 60637, USA
| | - Frederick A Matsen
- Computational Biology Program, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
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27
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Harris NL. Indolent lymphoma: follicular lymphoma and the microenvironment-insights from the microscope. HEMATOLOGY. AMERICAN SOCIETY OF HEMATOLOGY. EDUCATION PROGRAM 2014; 2014:158-162. [PMID: 25696849 DOI: 10.1182/asheducation-2014.1.158] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Follicular lymphomas (FLs) are neoplasms of germinal center (GC) B cells, which retain many of the morphologic, immunophenotypic, genetic, and functional features of normal GC B cells. Both normal GCs and neoplastic follicles of FL also contain non-neoplastic cells (microenvironment) that influence and are influenced by the GC and FL B cells and are likely important for tumor cell survival. Many insights into the nature of the GC/FL microenvironment have come from morphologic and immunophenotypic analysis, both before and after the discoveries from gene expression profiling. This chapter reviews what we have learned from the microscope and highlights the pitfalls involved in trying to enumerate cells in the microenvironment for clinical prognostication.
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Affiliation(s)
- Nancy Lee Harris
- Department of Pathology, Massachusetts General Hospital and Harvard Medical School, Boston, MA
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28
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Or-Guil M, Faro J. A major hindrance in antibody affinity maturation investigation: we never succeeded in falsifying the hypothesis of single-step selection. Front Immunol 2014; 5:237. [PMID: 24904585 PMCID: PMC4033600 DOI: 10.3389/fimmu.2014.00237] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2013] [Accepted: 05/07/2014] [Indexed: 01/17/2023] Open
Affiliation(s)
- Michal Or-Guil
- Systems Immunology Laboratory, Department of Biology, Humboldt-Universität zu Berlin , Berlin , Germany ; Research Center ImmunoSciences, Charité-Universitätsmedizin Berlin , Berlin , Germany
| | - Jose Faro
- Area of Immunology, Faculty of Biology, Biomedical Research Center (CINBIO), Universidade de Vigo , Vigo , Spain ; Instituto Biomédico de Vigo , Vigo , Spain ; Instituto Gulbenkian de Ciência , Oeiras , Portugal
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29
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Abstract
BACKGROUND Germinal Centers (GC) are short-lived micro-anatomical structures, within lymphoid organs, where affinity maturation is initiated. Theoretical modeling of the dynamics of the GC reaction including follicular CD4+ T helper and the recently described follicular regulatory CD4+ T cell populations, predicts that the intensity and life span of such reactions is driven by both types of T cells, yet controlled primarily by follicular regulatory CD4+ T cells. In order to calibrate GC models, it is necessary to properly analyze the kinetics of GC sizes. Presently, the estimation of spleen GC volumes relies upon confocal microscopy images from 20-30 slices spanning a depth of ~ 20 - 50 μm, whose GC areas are analyzed, slice-by-slice, for subsequent 3D reconstruction and quantification. The quantity of data to be analyzed from such images taken for kinetics experiments is usually prohibitively large to extract semi-manually with existing software. As a result, the entire procedure is highly time-consuming, and inaccurate, thereby motivating the need for a new software tool that can automatically identify and calculate the 3D spot volumes from GC multidimensional images. RESULTS We have developed pyBioImage, an open source cross platform image analysis software application, written in python with C extensions that is specifically tailored to the needs of immunologic research involving 4D imaging of GCs. The software provides 1) support for importing many multi-image formats, 2) basic image processing and analysis, and 3) the ExtractGC module, that allows for automatic analysis and visualization of extracted GC volumes from multidimensional confocal microscopy images. We present concrete examples of different microscopy image data sets of GC that have been used in experimental and theoretical studies of mouse model GC dynamics. CONCLUSIONS The pyBioImage software framework seeks to be a general purpose image application for immunological research based on 4D imaging. The ExtractGC module uses a novel clustering algorithm for automatically extracting quantitative spatial information of a large number of GCs from a collection of confocal microscopy images. In addition, the software provides 3D visualization of the GCs reconstructed from the image stacks. The application is available for public use at http://sourceforge.net/projects/pybioimage/.
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Affiliation(s)
- David N Olivieri
- School of Computer Engineering, University of Vigo, Ourense, Spain.
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30
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El Shikh MEM, Pitzalis C. Follicular dendritic cells in health and disease. Front Immunol 2012; 3:292. [PMID: 23049531 PMCID: PMC3448061 DOI: 10.3389/fimmu.2012.00292] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2012] [Accepted: 08/31/2012] [Indexed: 12/17/2022] Open
Abstract
Follicular dendritic cells (FDCs) are unique immune cells that contribute to the regulation of humoral immune responses. These cells are located in the B-cell follicles of secondary lymphoid tissues where they trap and retain antigens (Ags) in the form of highly immunogenic immune complexes (ICs) consisting of Ag plus specific antibody (Ab) and/or complement proteins. FDCs multimerize Ags and present them polyvalently to B-cells in periodically arranged arrays that extensively crosslink the B-cell receptors for Ag (BCRs). FDC-FcγRIIB mediates IC periodicity, and FDC-Ag presentation combined with other soluble and membrane bound signals contributed by FDCs, like FDC-BAFF, -IL-6, and -C4bBP, are essential for the induction of the germinal center (GC) reaction, the maintenance of serological memory, and the remarkable ability of FDC-Ags to induce specific Ab responses in the absence of cognate T-cell help. On the other hand, FDCs play a negative role in several disease conditions including chronic inflammatory diseases, autoimmune diseases, HIV/AIDS, prion diseases, and follicular lymphomas. Compared to other accessory immune cells, FDCs have received little attention, and their functions have not been fully elucidated. This review gives an overview of FDC structure, and recapitulates our current knowledge on the immunoregulatory functions of FDCs in health and disease. A better understanding of FDCs should permit better regulation of Ab responses to suit the therapeutic manipulation of regulated and dysregulated immune responses.
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Affiliation(s)
- Mohey Eldin M El Shikh
- Centre for Experimental Medicine and Rheumatology, William Harvey Research Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London London, UK
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31
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Shlomchik MJ, Weisel F. Germinal center selection and the development of memory B and plasma cells. Immunol Rev 2012; 247:52-63. [PMID: 22500831 DOI: 10.1111/j.1600-065x.2012.01124.x] [Citation(s) in RCA: 308] [Impact Index Per Article: 25.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
A hallmark of adaptive immune responses is the generation of long-lived protection after primary exposure to a pathogen. In humoral responses, this protection stems from a combination of sustained antibody titers and long-lived memory B cells (MBCs), with the former deriving from long-lived plasma cells (PCs). Both types of cell are thought to primarily derive from the germinal center (GC), a unique structure that forms during the immune response to many types of antigenic stimuli. GCs are seeded by antigen-specific B and T cells that were previously activated in the early stages of the response. The GC does not directly or immediately generate effector function; rather, it is a site of intense B-cell proliferation and cell death. GC B cells undergo both somatic hypermutation and isotype switch, and a Darwinian process very efficiently selects B cells with higher fitness for survival and expansion. GC B cells adopt a unique activation and transcriptional state, and the cells become poised to differentiate to either MBCs or PCs. Despite this general understanding of the events in the GC, the mechanisms that control both affinity selection as well as differentiation have not been well worked out. In this review, we address what is known about what determines whether GC B cells become MBCs or PCs. This is discussed in the broader context of the origins of both cell types, whether from the GC or potentially other sources. We present a model encompassing recent data from several laboratories including our own that suggests that the GC undergoes a temporal switch that alters the nature of its output from MBCs to PCs as the response progresses. We will discuss B-cell receptor signaling in the GC as it relates to potential mechanisms for affinity-based selection during the reaction.
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Affiliation(s)
- Mark J Shlomchik
- Department of Laboratory Medicine, Yale University School of Medicine, New Haven, CT 06520-8035, USA.
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32
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Zotos D, Tarlinton DM. Determining germinal centre B cell fate. Trends Immunol 2012; 33:281-8. [DOI: 10.1016/j.it.2012.04.003] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2012] [Revised: 04/03/2012] [Accepted: 04/05/2012] [Indexed: 12/13/2022]
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