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Hou Y, Treanor B. DNA origami: Interrogating the nano-landscape of immune receptor activation. Biophys J 2024; 123:2211-2223. [PMID: 37838832 PMCID: PMC11331043 DOI: 10.1016/j.bpj.2023.10.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Revised: 09/22/2023] [Accepted: 10/12/2023] [Indexed: 10/16/2023] Open
Abstract
The immune response is orchestrated by elaborate protein interaction networks that interweave ligand-mediated receptor reorganization with signaling cascades. While the biochemical processes have been extensively investigated, delineating the biophysical principles governing immune receptor activation has remained challenging due to design limitations of traditional ligand display platforms. These constraints have been overcome by advances in DNA origami nanotechnology, enabling unprecedented control over ligand geometry on configurable scaffolds. It is now possible to systematically dissect the independent roles of ligand stoichiometry, spatial distribution, and rigidity in immune receptor activation, signaling, and cooperativity. In this review, we highlight pioneering efforts in manipulating the ligand presentation landscape to understand immune receptor triggering and to engineer functional immune responses.
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Affiliation(s)
- Yuchen Hou
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario.
| | - Bebhinn Treanor
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario; Department of Biological Sciences, University of Toronto Scarborough, Toronto, Ontario; Department of Immunology, University of Toronto, Toronto, Ontario.
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2
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Ortiz Y, Anasti K, Pane AK, Cronin K, Alam SM, Reth M. The CH1 domain influences the expression and antigen sensing of the HIV-specific CH31 IgM-BCR and IgG-BCR. Proc Natl Acad Sci U S A 2024; 121:e2404728121. [PMID: 39042672 PMCID: PMC11295018 DOI: 10.1073/pnas.2404728121] [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: 03/06/2024] [Accepted: 06/25/2024] [Indexed: 07/25/2024] Open
Abstract
How different classes of the B cell antigen receptor (BCR) sense viral antigens used in vaccination protocols is poorly understood. Here, we study antigen binding and sensing of human Ramos B cells expressing a BCR of either the IgM or IgG1 class with specificity for the CD4-binding-site of the envelope (Env) protein of the HIV-1. Both BCRs carry an identical antigen binding site derived from the broad neutralizing antibody (bnAb) CH31. We find a five times higher expression of the IgG1-BCR in comparison to the IgM-BCR on the surface of transfected Ramos B cells. The two BCR classes also differ from each other in their interaction with cognate HIV Env antigens in that the IgG1-BCR and IgM-BCR bind preferentially to polyvalent and monovalent antigens, respectively. By generating an IgM/IgG1 chimeric BCR, we found that the class-specific BCR expression and antigen-sensing behavior can be transferred with the CH1γ domain from the IgG1-BCR to the IgM-BCR. Thus, the class of CH1 domain has an impact on BCR assembly and expression as well as on antigen sensing.
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Affiliation(s)
- Yaneth Ortiz
- Department of Molecular Immunology, Biology III, Faculty of Biology, University of Freiburg, Freiburg79104, Germany
- Faculty of Biology, Signalling Research Centers Centre for Integrative Biological Signalling Studies and Centre for Biological Signalling Studies, University of Freiburg, Freiburg79104, Germany
| | - Kara Anasti
- Department of Medicine & Pathology, Human Vaccine Institute, Duke University, Durham, NC27703
| | - Advaiti K. Pane
- Department of Medicine & Pathology, Human Vaccine Institute, Duke University, Durham, NC27703
| | - Kenneth Cronin
- Department of Medicine & Pathology, Human Vaccine Institute, Duke University, Durham, NC27703
| | - S. Munir Alam
- Department of Medicine & Pathology, Human Vaccine Institute, Duke University, Durham, NC27703
- Deparment of Medicine and Pathology, Duke University, DurhamNC27703
| | - Michael Reth
- Department of Molecular Immunology, Biology III, Faculty of Biology, University of Freiburg, Freiburg79104, Germany
- Faculty of Biology, Signalling Research Centers Centre for Integrative Biological Signalling Studies and Centre for Biological Signalling Studies, University of Freiburg, Freiburg79104, Germany
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3
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Sánchez MF, Faria S, Frühschulz S, Werkmann L, Winter C, Karimian T, Lanzerstorfer P, Plochberger B, Weghuber J, Tampé R. Engineering Mesoscale T Cell Receptor Clustering by Plug-and-Play Nanotools. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024:e2310407. [PMID: 38924642 DOI: 10.1002/adma.202310407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2023] [Revised: 06/10/2024] [Indexed: 06/28/2024]
Abstract
T cell receptor (TCR) clustering and formation of an immune synapse are crucial for TCR signaling. However, limited information is available about these dynamic assemblies and their connection to transmembrane signaling. In this work, TCR clustering is controlled via plug-and-play nanotools based on an engineered irreversible conjugation pair and a peptide-loaded major histocompatibility complex (pMHC) molecule to compare receptor assembly in a ligand (pMHC)-induced or ligand-independent manner. A streptavidin-binding peptide displayed in both tools enabled their anchoring in streptavidin-pre-structured matrices. Strikingly, pMHC-induced clustering in the confined regions exhibit higher density and dynamics than the ligand-free approach, indicating that the size and architecture of the pMHC ligand influences TCR assembly. This approach enables the control of membrane receptor clustering with high specificity and provides the possibility to explore different modalities of receptor activation.
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Affiliation(s)
- M Florencia Sánchez
- Institute of Biochemistry, Biocenter, Goethe University Frankfurt, Max-von-Laue-Str. 9, 60438, Frankfurt am Main, Germany
| | - Sevi Faria
- Institute of Biochemistry, Biocenter, Goethe University Frankfurt, Max-von-Laue-Str. 9, 60438, Frankfurt am Main, Germany
| | - Stefan Frühschulz
- Institute of Biochemistry, Biocenter, Goethe University Frankfurt, Max-von-Laue-Str. 9, 60438, Frankfurt am Main, Germany
| | - Lars Werkmann
- Institute of Biochemistry, Biocenter, Goethe University Frankfurt, Max-von-Laue-Str. 9, 60438, Frankfurt am Main, Germany
| | - Christian Winter
- Institute of Biochemistry, Biocenter, Goethe University Frankfurt, Max-von-Laue-Str. 9, 60438, Frankfurt am Main, Germany
| | - Tina Karimian
- Center of Excellence Food Technology and Nutrition, University of Applied Sciences Upper Austria, Wels, 4600, Austria
| | - Peter Lanzerstorfer
- Center of Excellence Food Technology and Nutrition, University of Applied Sciences Upper Austria, Wels, 4600, Austria
| | - Birgit Plochberger
- University of Applied Sciences Upper Austria, Campus Linz, Linz, 4020, Austria
- Ludwig Boltzmann Institute for Experimental and Clinical Traumatology, Donaueschingenstr. 13, Vienna, 1200, Austria
| | - Julian Weghuber
- Center of Excellence Food Technology and Nutrition, University of Applied Sciences Upper Austria, Wels, 4600, Austria
- FFoQSI - Austrian Competence Centre for Feed and Food Quality, Safety & Innovation, FFoQSI GmbH, Technopark 1D, Tulln an der Donau, 3430, Austria
| | - Robert Tampé
- Institute of Biochemistry, Biocenter, Goethe University Frankfurt, Max-von-Laue-Str. 9, 60438, Frankfurt am Main, Germany
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4
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Sun W, Gui J, Wan K, Cai Y, Dong X, Yu G, Zheng C, Feng Z, Shuai L. Causal effects of immune cell surface antigens and functional outcome after ischemic stroke: a Mendelian randomization study. Front Immunol 2024; 15:1353034. [PMID: 38562935 PMCID: PMC10982317 DOI: 10.3389/fimmu.2024.1353034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2023] [Accepted: 02/14/2024] [Indexed: 04/04/2024] Open
Abstract
Objective While observational studies link immune cells with post-stroke functional outcome, the underlying immune mechanisms are not well understood. Immune cell surface antigens are actively involved in the biological behavior of immune cells, investigating immune cell surface antigens could deepen our comprehension of their role and biological processes in stroke recovery. Therefore, we aimed to investigate the immunological basis of stroke outcome by exploring the causal relationship between immune cell surface antigens and functional outcome after ischemic stroke in a Mendelian randomization study. Methods Genetic variants related to immune cell surface antigens and post-stroke functional outcome were selected for two-sample Mendelian randomization (MR) analysis. 389 fluorescence intensities (MFIs) with surface antigens were included. Inverse variance weighted (IVW) modeling was used as the primary MR method to estimate the causal effect of exposure on the outcome, followed by several alternative methods and sensitivity analyses. Additional analysis of the association between immune cell surface antigens and risk of ischemic stroke for assessment of collider bias. Results We found that suggestive associations between CD20 on switched memory B cell (OR = 1.16, 95% CI: 1.01-1.34, p = 0.036) and PDL-1 on monocyte (OR = 1.32, 95% CI: 1.04-1.66, p = 0.022) and poor post-stroke functional outcome, whereas CD25 on CD39+ resting Treg (OR = 0.77, 95% CI: 0.62-0.96, p = 0.017) was suggestively associated with good post-stroke functional outcome. Conclusion The elevated CD20 on switched memory B cell, PDL-1 on monocyte, and CD25 on CD39+ resting Treg may be novel biomarkers and potential causal factors influencing post-stroke functional outcome.
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Affiliation(s)
- Weiming Sun
- Department of Rehabilitation Medicine, The First Affiliated Hospital, Jiangxi Medical College, Nanchang University, Nanchang, China
- The First Clinical Medical College, Jiangxi Medical College, Nanchang University, Nanchang, China
- Postdoctoral Innovation Practice Base, The First Affiliated Hospital, Jiangxi Medical College, Nanchang University, Nanchang, China
| | - Jiawei Gui
- HuanKui Academy, Jiangxi Medical College, Nanchang University, Nanchang, China
| | - Keqi Wan
- Department of Rehabilitation Medicine, The First Affiliated Hospital, Jiangxi Medical College, Nanchang University, Nanchang, China
- The First Clinical Medical College, Jiangxi Medical College, Nanchang University, Nanchang, China
| | - Yize Cai
- School of Public Policy, Nanchang University, Nanchang, China
| | - Xiangli Dong
- Department of Psychosomatic Medicine, The Second Affiliated Hospital, Jiangxi Medical College, Nanchang University, Nanchang, China
| | - Guohua Yu
- Department of Rehabilitation Medicine, The First Affiliated Hospital, Jiangxi Medical College, Nanchang University, Nanchang, China
- The First Clinical Medical College, Jiangxi Medical College, Nanchang University, Nanchang, China
| | - Chafeng Zheng
- Department of Rehabilitation Medicine, The First Affiliated Hospital, Jiangxi Medical College, Nanchang University, Nanchang, China
- The First Clinical Medical College, Jiangxi Medical College, Nanchang University, Nanchang, China
| | - Zhen Feng
- Department of Rehabilitation Medicine, The First Affiliated Hospital, Jiangxi Medical College, Nanchang University, Nanchang, China
- The First Clinical Medical College, Jiangxi Medical College, Nanchang University, Nanchang, China
- Postdoctoral Innovation Practice Base, The First Affiliated Hospital, Jiangxi Medical College, Nanchang University, Nanchang, China
| | - Lang Shuai
- Department of Rehabilitation Medicine, The First Affiliated Hospital, Jiangxi Medical College, Nanchang University, Nanchang, China
- The First Clinical Medical College, Jiangxi Medical College, Nanchang University, Nanchang, China
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Querol Cano L, Dunlock VME, Schwerdtfeger F, van Spriel AB. Membrane organization by tetraspanins and galectins shapes lymphocyte function. Nat Rev Immunol 2024; 24:193-212. [PMID: 37758850 DOI: 10.1038/s41577-023-00935-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/15/2023] [Indexed: 09/29/2023]
Abstract
Immune receptors are not randomly distributed at the plasma membrane of lymphocytes but are segregated into specialized domains that function as platforms to initiate signalling, as exemplified by the B cell or T cell receptor complex and the immunological synapse. 'Membrane-organizing proteins' and, in particular, tetraspanins and galectins, are crucial for controlling the spatiotemporal organization of immune receptors and other signalling proteins. Deficiencies in specific tetraspanins and galectins result in impaired immune synapse formation, lymphocyte proliferation, antibody production and migration, which can lead to impaired immunity, tumour development and autoimmunity. In contrast to conventional ligand-receptor interactions, membrane organizers interact in cis (on the same cell) and modulate receptor clustering, receptor dynamics and intracellular signalling. New findings have uncovered their complex and dynamic nature, revealing shared binding partners and collaborative activity in determining the composition of membrane domains. Therefore, immune receptors should not be envisaged as independent entities and instead should be studied in the context of their spatial organization in the lymphocyte membrane. We advocate for a novel approach to study lymphocyte function by globally analysing the role of membrane organizers in the assembly of different membrane complexes and discuss opportunities to develop therapeutic approaches that act via the modulation of membrane organization.
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Affiliation(s)
- Laia Querol Cano
- Department of Medical BioSciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Vera-Marie E Dunlock
- Department of Medical BioSciences, Radboud University Medical Center, Nijmegen, The Netherlands
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Fabian Schwerdtfeger
- Department of Medical BioSciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Annemiek B van Spriel
- Department of Medical BioSciences, Radboud University Medical Center, Nijmegen, The Netherlands.
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Hu W, Song X, Yu H, Fan S, Shi A, Sun J, Wang H, Zhao L, Zhao Y. Suppression of B-Cell Activation by Human Cord Blood-Derived Stem Cells (CB-SCs) through the Galectin-9-Dependent Mechanism. Int J Mol Sci 2024; 25:1830. [PMID: 38339108 PMCID: PMC10855911 DOI: 10.3390/ijms25031830] [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: 01/09/2024] [Revised: 01/29/2024] [Accepted: 01/30/2024] [Indexed: 02/12/2024] Open
Abstract
We developed the Stem Cell Educator therapy among multiple clinical trials based on the immune modulations of multipotent cord blood-derived stem cells (CB-SCs) on different compartments of immune cells, such as T cells and monocytes/macrophages, in type 1 diabetes and other autoimmune diseases. However, the effects of CB-SCs on the B cells remained unclear. To better understand the molecular mechanisms underlying the immune education of CB-SCs, we explored the modulations of CB-SCs on human B cells. CB-SCs were isolated from human cord blood units and confirmed by flow cytometry with different markers for their purity. B cells were purified by using anti-CD19 immunomagnetic beads from human peripheral blood mononuclear cells (PBMCs). Next, the activated B cells were treated in the presence or absence of coculture with CB-SCs for 7 days before undergoing flow cytometry analysis of phenotypic changes with different markers. Reverse transcription-polymerase chain reaction (RT-PCR) was utilized to evaluate the levels of galectin expressions on CB-SCs with or without treatment of activated B cells in order to find the key galectin that was contributing to the B-cell modulation. Flow cytometry demonstrated that the proliferation of activated B cells was markedly suppressed in the presence of CB-SCs, leading to the downregulation of immunoglobulin production from the activated B cells. Phenotypic analysis revealed that treatment with CB-SCs increased the percentage of IgD+CD27- naïve B cells, but decreased the percentage of IgD-CD27+ switched B cells. The transwell assay showed that the immune suppression of CB-SCs on B cells was dependent on the galectin-9 molecule, as confirmed by the blocking experiment with the anti-galectin-9 monoclonal antibody. Mechanistic studies demonstrated that both calcium levels of cytoplasm and mitochondria were downregulated after the treatment with CB-SCs, causing the decline in mitochondrial membrane potential in the activated B cells. Western blot exhibited that the levels of phosphorylated Akt and Erk1/2 signaling proteins in the activated B cells were also markedly reduced in the presence of CB-SCs. CB-SCs displayed multiple immune modulations on B cells through the galectin-9-mediated mechanism and calcium flux/Akt/Erk1/2 signaling pathways. The data advance our current understanding of the molecular mechanisms underlying the Stem Cell Educator therapy to treat autoimmune diseases in clinics.
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Affiliation(s)
- Wei Hu
- Center for Discovery and Innovation, Hackensack Meridian Health, Nutley, NJ 07110, USA; (W.H.)
| | - Xiang Song
- Center for Discovery and Innovation, Hackensack Meridian Health, Nutley, NJ 07110, USA; (W.H.)
| | - Haibo Yu
- Center for Discovery and Innovation, Hackensack Meridian Health, Nutley, NJ 07110, USA; (W.H.)
| | - Sophia Fan
- Throne Biotechnologies, Paramus, NJ 07652, USA
| | - Andrew Shi
- Throne Biotechnologies, Paramus, NJ 07652, USA
| | - Jingyu Sun
- Department of Chemistry and Chemical Biology, Stevens Institute of Technology, Hoboken, NJ 07030, USA; (J.S.); (H.W.)
| | - Hongjun Wang
- Department of Chemistry and Chemical Biology, Stevens Institute of Technology, Hoboken, NJ 07030, USA; (J.S.); (H.W.)
| | - Laura Zhao
- Throne Biotechnologies, Paramus, NJ 07652, USA
| | - Yong Zhao
- Center for Discovery and Innovation, Hackensack Meridian Health, Nutley, NJ 07110, USA; (W.H.)
- Throne Biotechnologies, Paramus, NJ 07652, USA
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7
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Neys SFH, Heutz JW, van Hulst JAC, Vink M, Bergen IM, de Jong PHP, Lubberts E, Hendriks RW, Corneth OBJ. Aberrant B cell receptor signaling in circulating naïve and IgA + memory B cells from newly-diagnosed autoantibody-positive rheumatoid arthritis patients. J Autoimmun 2024; 143:103168. [PMID: 38350168 DOI: 10.1016/j.jaut.2024.103168] [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: 10/13/2023] [Revised: 01/08/2024] [Accepted: 01/12/2024] [Indexed: 02/15/2024]
Abstract
OBJECTIVE Altered B cell receptor (BCR) signaling has been implicated in the pathogenesis of rheumatoid arthritis (RA). Here we aimed to identify signaling aberrations in autoantibody-positive and autoantibody-negative RA patients by performing a comprehensive analysis of the BCR signaling cascade in different B cell subsets. METHODS We first optimized phosphoflow cytometry for an in-depth analysis of BCR signaling across immunoglobulin isotypes in healthy donors. Subsequently, we compared BCR signaling in circulating B cell subsets from treatment-naïve, newly-diagnosed autoantibody-positive RA and autoantibody-negative RA patients and healthy controls (HCs). RESULTS We observed subset-specific phosphorylation patterns of the BCR signalosome in circulating B cells from healthy donors. Compared with HCs, autoantibody-positive RA patients displayed enhanced responses to BCR stimulation for multiple signaling proteins, specifically in naïve and IgA+ memory B cells. Whereas in unstimulated healthy donor B cells, the phosphorylation status of individual signaling proteins showed only limited correlation, BCR stimulation enhanced the interconnectivity in phosphorylation within the BCR signalosome. However, this strong interconnectivity within the BCR signalosome in stimulated B cells from HCs was lost in RA, especially in autoantibody-positive RA patients. Finally, we observed strong correlations between SYK and BTK protein expression, and IgA and IgG anti-citrullinated protein antibody concentrations in serum from autoantibody-positive RA patients. CONCLUSION Collectively, the isotype-specific analysis of multiple key components of the BCR signalosome identified aberrant BCR signaling responses in treatment-naïve autoantibody-positive RA patients, particularly in naïve B cells and IgA+ memory B cells. Our findings support differential involvement of dysregulated BCR signaling in the pathogenesis of autoantibody-positive and autoantibody-negative RA.
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Affiliation(s)
- Stefan F H Neys
- Department of Pulmonary Medicine, Erasmus MC Rotterdam, Rotterdam, the Netherlands
| | - Judith W Heutz
- Department of Rheumatology, Erasmus MC Rotterdam, Rotterdam, the Netherlands
| | | | - Madelief Vink
- Department of Pulmonary Medicine, Erasmus MC Rotterdam, Rotterdam, the Netherlands
| | - Ingrid M Bergen
- Department of Pulmonary Medicine, Erasmus MC Rotterdam, Rotterdam, the Netherlands
| | - Pascal H P de Jong
- Department of Rheumatology, Erasmus MC Rotterdam, Rotterdam, the Netherlands
| | - Erik Lubberts
- Department of Rheumatology, Erasmus MC Rotterdam, Rotterdam, the Netherlands
| | - Rudi W Hendriks
- Department of Pulmonary Medicine, Erasmus MC Rotterdam, Rotterdam, the Netherlands
| | - Odilia B J Corneth
- Department of Pulmonary Medicine, Erasmus MC Rotterdam, Rotterdam, the Netherlands.
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8
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Evans JP, Liu SL. Challenges and Prospects in Developing Future SARS-CoV-2 Vaccines: Overcoming Original Antigenic Sin and Inducing Broadly Neutralizing Antibodies. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2023; 211:1459-1467. [PMID: 37931210 DOI: 10.4049/jimmunol.2300315] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Accepted: 06/27/2023] [Indexed: 11/08/2023]
Abstract
The impacts of the COVID-19 pandemic led to the development of several effective SARS-CoV-2 vaccines. However, waning vaccine efficacy as well as the antigenic drift of SARS-CoV-2 variants has diminished vaccine efficacy against SARS-CoV-2 infection and may threaten public health. Increasing interest has been given to the development of a next generation of SARS-CoV-2 vaccines with increased breadth and effectiveness against SARS-CoV-2 infection. In this Brief Review, we discuss recent work on the development of these next-generation vaccines and on the nature of the immune response to SARS-CoV-2. We examine recent work to develop pan-coronavirus vaccines as well as to develop mucosal vaccines. We further discuss challenges associated with the development of novel vaccines including the need to overcome "original antigenic sin" and highlight areas requiring further investigation. We place this work in the context of SARS-CoV-2 evolution to inform how the implementation of future vaccine platforms may impact human health.
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Affiliation(s)
- John P Evans
- Center for Retrovirus Research, The Ohio State University, Columbus, OH
- Department of Veterinary Biosciences, The Ohio State University, Columbus, OH
- Molecular, Cellular, and Developmental Biology Program, The Ohio State University, Columbus, OH
| | - Shan-Lu Liu
- Center for Retrovirus Research, The Ohio State University, Columbus, OH
- Department of Veterinary Biosciences, The Ohio State University, Columbus, OH
- Viruses and Emerging Pathogens Program, Infectious Diseases Institute, The Ohio State University, Columbus, OH
- Department of Microbial Infection and Immunity, The Ohio State University, Columbus, OH
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9
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Brooks JF, Riggs J, Mueller JL, Mathenge R, Wholey WY, Meyer AR, Yoda ST, Vykunta VS, Nielsen HV, Cheng W, Zikherman J. Molecular basis for potent B cell responses to antigen displayed on particles of viral size. Nat Immunol 2023; 24:1762-1777. [PMID: 37653247 PMCID: PMC10950062 DOI: 10.1038/s41590-023-01597-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2023] [Accepted: 07/18/2023] [Indexed: 09/02/2023]
Abstract
Multivalent viral epitopes induce rapid, robust and T cell-independent humoral immune responses, but the biochemical basis for such potency remains incompletely understood. We take advantage of a set of liposomes of viral size engineered to display affinity mutants of the model antigen (Ag) hen egg lysozyme. Particulate Ag induces potent 'all-or-none' B cell responses that are density dependent but affinity independent. Unlike soluble Ag, particulate Ag induces signal amplification downstream of the B cell receptor by selectively evading LYN-dependent inhibitory pathways and maximally activates NF-κB in a manner that mimics T cell help. Such signaling induces MYC expression and enables even low doses of particulate Ag to trigger robust B cell proliferation in vivo in the absence of adjuvant. We uncover a molecular basis for highly sensitive B cell responses to viral Ag display that is independent of encapsulated nucleic acids and is not merely accounted for by avidity and B cell receptor cross-linking.
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Affiliation(s)
- Jeremy F Brooks
- Division of Rheumatology, Rosalind Russell and Ephraim P. Engleman Rheumatology Research Center, Department of Medicine, University of California, San Francisco, CA, USA
| | - Julianne Riggs
- Division of Rheumatology, Rosalind Russell and Ephraim P. Engleman Rheumatology Research Center, Department of Medicine, University of California, San Francisco, CA, USA
- Biomedical Sciences Graduate Program, University of California, San Francisco, CA, USA
| | - James L Mueller
- Division of Rheumatology, Rosalind Russell and Ephraim P. Engleman Rheumatology Research Center, Department of Medicine, University of California, San Francisco, CA, USA
| | - Raisa Mathenge
- Division of Rheumatology, Rosalind Russell and Ephraim P. Engleman Rheumatology Research Center, Department of Medicine, University of California, San Francisco, CA, USA
| | - Wei-Yun Wholey
- Department of Pharmaceutical Sciences, University of Michigan, Ann Arbor, MI, USA
| | - Alexander R Meyer
- Department of Pharmaceutical Sciences, University of Michigan, Ann Arbor, MI, USA
| | - Sekou-Tidiane Yoda
- Department of Pharmaceutical Sciences, University of Michigan, Ann Arbor, MI, USA
| | - Vivasvan S Vykunta
- Division of Rheumatology, Rosalind Russell and Ephraim P. Engleman Rheumatology Research Center, Department of Medicine, University of California, San Francisco, CA, USA
| | - Hailyn V Nielsen
- Division of Rheumatology, Rosalind Russell and Ephraim P. Engleman Rheumatology Research Center, Department of Medicine, University of California, San Francisco, CA, USA
| | - Wei Cheng
- Department of Pharmaceutical Sciences, University of Michigan, Ann Arbor, MI, USA.
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, MI, USA.
| | - Julie Zikherman
- Division of Rheumatology, Rosalind Russell and Ephraim P. Engleman Rheumatology Research Center, Department of Medicine, University of California, San Francisco, CA, USA.
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10
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Mamidi MK, Huang J, Honjo K, Li R, Tabengwa EM, Neeli I, Randall NL, Ponnuchetty MV, Radic M, Leu CM, Davis RS. FCRL1 immunoregulation in B cell development and malignancy. Front Immunol 2023; 14:1251127. [PMID: 37822931 PMCID: PMC10562807 DOI: 10.3389/fimmu.2023.1251127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Accepted: 09/01/2023] [Indexed: 10/13/2023] Open
Abstract
Immunotherapeutic targeting of surface regulatory proteins and pharmacologic inhibition of critical signaling pathways has dramatically shifted our approach to the care of individuals with B cell malignancies. This evolution in therapy reflects the central role of the B cell receptor (BCR) signaling complex and its co-receptors in the pathogenesis of B lineage leukemias and lymphomas. Members of the Fc receptor-like gene family (FCRL1-6) encode cell surface receptors with complex tyrosine-based regulation that are preferentially expressed by B cells. Among them, FCRL1 expression peaks on naïve and memory B cells and is unique in terms of its intracellular co-activation potential. Recent studies in human and mouse models indicate that FCRL1 contributes to the formation of the BCR signalosome, modulates B cell signaling, and promotes humoral responses. Progress in understanding its regulatory properties, along with evidence for its over-expression by mature B cell leukemias and lymphomas, collectively imply important yet unmet opportunities for FCRL1 in B cell development and transformation. Here we review recent advances in FCRL1 biology and highlight its emerging significance as a promising biomarker and therapeutic target in B cell lymphoproliferative disorders.
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Affiliation(s)
- Murali K. Mamidi
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Jifeng Huang
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Kazuhito Honjo
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Ran Li
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Edlue M. Tabengwa
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Indira Neeli
- Department of Microbiology, Immunology and Biochemistry, University of Tennessee Health Science Center, Memphis, TN, United States
| | - Nar’asha L. Randall
- Department of Microbiology, Immunology and Biochemistry, University of Tennessee Health Science Center, Memphis, TN, United States
| | - Manasa V. Ponnuchetty
- Department of Microbiology, Immunology and Biochemistry, University of Tennessee Health Science Center, Memphis, TN, United States
| | - Marko Radic
- Department of Microbiology, Immunology and Biochemistry, University of Tennessee Health Science Center, Memphis, TN, United States
| | - Chuen-Miin Leu
- Institute of Microbiology and Immunology, National Yang Ming ChiaoTung University, Taipei, Taiwan
| | - Randall S. Davis
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States
- Departments of Microbiology, and Biochemistry & Molecular Genetics, University of Alabama at Birmingham, Birmingham, AL, United States
- O’Neal Comprehensive Cancer Center, University of Alabama at Birmingham, Birmingham, AL, United States
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11
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Mazzarello AN, Fitch M, Cardillo M, Ng A, Bhuiya S, Sharma E, Bagnara D, Kolitz JE, Barrientos JC, Allen SL, Rai KR, Rhodes J, Hellerstein MK, Chiorazzi N. Characterization of the Intraclonal Complexity of Chronic Lymphocytic Leukemia B Cells: Potential Influences of B-Cell Receptor Crosstalk with Other Stimuli. Cancers (Basel) 2023; 15:4706. [PMID: 37835400 PMCID: PMC10571896 DOI: 10.3390/cancers15194706] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Revised: 09/15/2023] [Accepted: 09/18/2023] [Indexed: 10/15/2023] Open
Abstract
Chronic lymphocytic leukemia (CLL) clones contain subpopulations differing in time since the last cell division ("age"): recently born, proliferative (PF; CXCR4DimCD5Bright), intermediate (IF; CXCR4IntCD5Int), and resting (RF; CXCR4BrightCD5Dim) fractions. Herein, we used deuterium (2H) incorporation into newly synthesized DNA in patients to refine the kinetics of CLL subpopulations by characterizing two additional CXCR4/CD5 fractions, i.e., double dim (DDF; CXCR4DimCD5Dim) and double bright (DBF; CXCR4BrightCD5Bright); and intraclonal fractions differing in surface membrane (sm) IgM and IgD densities. Although DDF was enriched in recently divided cells and DBF in older cells, PF and RF remained the most enriched in youngest and oldest cells, respectively. Similarly, smIgMHigh and smIgDHigh cells were the youngest, and smIgMLow and smIgDLow were the oldest, when using smIG levels as discriminator. Surprisingly, the cells closest to the last stimulatory event bore high levels of smIG, and stimulating via TLR9 and smIG yielded a phenotype more consistent with the in vivo setting. Finally, older cells were less sensitive to in vivo inhibition by ibrutinib. Collectively, these data define additional intraclonal subpopulations with divergent ages and phenotypes and suggest that BCR engagement alone is not responsible for the smIG levels found in vivo, and the differential sensitivity of distinct fractions to ibrutinib might account, in part, for therapeutic relapse.
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Affiliation(s)
- Andrea N. Mazzarello
- The Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY 11030, USA
- Department of Experimental Medicine, University of Genova, 16132 Genova, Italy
| | - Mark Fitch
- Department of Nutritional Sciences & Toxicology, University of California at Berkeley, Berkeley, CA 94720, USA
| | - Martina Cardillo
- The Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY 11030, USA
| | - Anita Ng
- The Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY 11030, USA
| | - Sabreen Bhuiya
- The Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY 11030, USA
| | - Esha Sharma
- The Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY 11030, USA
| | - Davide Bagnara
- The Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY 11030, USA
- Department of Experimental Medicine, University of Genova, 16132 Genova, Italy
| | - Jonathan E. Kolitz
- The Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY 11030, USA
- Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY 11549, USA
| | - Jacqueline C. Barrientos
- The Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY 11030, USA
- Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY 11549, USA
| | - Steven L. Allen
- The Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY 11030, USA
- Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY 11549, USA
| | - Kanti R. Rai
- The Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY 11030, USA
- Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY 11549, USA
| | - Joanna Rhodes
- The Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY 11030, USA
| | - Marc K. Hellerstein
- Department of Nutritional Sciences & Toxicology, University of California at Berkeley, Berkeley, CA 94720, USA
| | - Nicholas Chiorazzi
- The Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY 11030, USA
- Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY 11549, USA
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12
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Reth M. Discovering immunoreceptor coupling and organization motifs. Front Immunol 2023; 14:1253412. [PMID: 37731510 PMCID: PMC10507400 DOI: 10.3389/fimmu.2023.1253412] [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: 07/05/2023] [Accepted: 08/11/2023] [Indexed: 09/22/2023] Open
Abstract
The recently determined cryo-EM structures of the T cell antigen receptor (TCR) and B cell antigen receptor (BCR) show in molecular details the interactions of the ligand-binding part with the signaling subunits but they do not reveal the signaling mechanism of these antigen receptors. Without knowing the molecular basis of antigen sensing by these receptors, a rational design of optimal vaccines is not possible. The existence of conserved amino acids (AAs) that are not involved in the subunit interaction suggests that antigen receptors form higher complexes and/or have lateral interactors that control their activity. Here, I describe evolutionary conserved leucine zipper (LZ) motifs within the transmembrane domains (TMD) of antigen and coreceptor components that are likely to be involved in the oligomerization and lateral interaction of antigen receptor complexes on T and B cells. These immunoreceptor coupling and organization motifs (ICOMs) are also found within the TMDs of other important receptor types and viral envelope proteins. This discovery suggests that antigen receptors do not function as isolated entities but rather as part of an ICOM-based interactome that controls their nanoscale organization on resting cells and their dynamic remodeling on activated lymphocytes.
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Affiliation(s)
- Michael Reth
- Department of Molecular Immunology, Biology III, Faculty of Biology, University of Freiburg, Freiburg, Germany
- Signaling Research Centers CIBSS and BIOSS, University of Freiburg, Freiburg, Germany
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13
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Shelby SA, Castello-Serrano I, Wisser KC, Levental I, Veatch SL. Membrane phase separation drives responsive assembly of receptor signaling domains. Nat Chem Biol 2023; 19:750-758. [PMID: 36997644 PMCID: PMC10771812 DOI: 10.1038/s41589-023-01268-8] [Citation(s) in RCA: 43] [Impact Index Per Article: 43.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Accepted: 01/17/2023] [Indexed: 04/01/2023]
Abstract
Plasma membrane heterogeneity has been tied to a litany of cellular functions and is often explained by analogy to membrane phase separation; however, models based on phase separation alone fall short of describing the rich organization available within cell membranes. Here we present comprehensive experimental evidence motivating an updated model of plasma membrane heterogeneity in which membrane domains assemble in response to protein scaffolds. Quantitative super-resolution nanoscopy measurements in live B lymphocytes detect membrane domains that emerge upon clustering B cell receptors (BCRs). These domains enrich and retain membrane proteins based on their preference for the liquid-ordered phase. Unlike phase-separated membranes that consist of binary phases with defined compositions, membrane composition at BCR clusters is modulated through the protein constituents in clusters and the composition of the membrane overall. This tunable domain structure is detected through the variable sorting of membrane probes and impacts the magnitude of BCR activation.
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Affiliation(s)
- Sarah A Shelby
- Program in Biophysics, University of Michigan, Ann Arbor, MI, USA
- Department of Biochemistry & Cellular and Molecular Biology, University of Tennessee Knoxville, Knoxville, TN, USA
| | - Ivan Castello-Serrano
- Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, VA, USA
| | | | - Ilya Levental
- Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, VA, USA
| | - Sarah L Veatch
- Program in Biophysics, University of Michigan, Ann Arbor, MI, USA.
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14
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Brooks JF, Riggs J, Mueller JL, Mathenge R, Wholey WY, Yoda ST, Vykunta VS, Cheng W, Zikherman J. Molecular basis for potent B cell responses to antigen displayed on particles of viral size. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.02.15.528761. [PMID: 36824873 PMCID: PMC9949087 DOI: 10.1101/2023.02.15.528761] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Although it has long been appreciated that multivalent antigens - and particularly viral epitope display - produce extremely rapid, robust, and T-independent humoral immune responses, the biochemical basis for such potency has been incompletely understood. Here we take advantage of a set of neutral liposomes of viral size that are engineered to display affinity mutants of the model antigen (Ag) hen egg lysozyme at precisely varied density. We show that particulate Ag display by liposomes induces highly potent B cell responses that are dose-and density-dependent but affinity-independent. Titrating dose of particulate, but not soluble, Ag reveals bimodal Erk phosphorylation and cytosolic calcium increases. Particulate Ag induces signal amplification downstream of the B cell receptor (BCR) by selectively evading LYN-dependent inhibitory pathways, but in vitro potency is independent of CD19. Importantly, Ag display on viral-sized particles signals independently of MYD88 and IRAK1/4, but activates NF- κ B robustly in a manner that mimics T cell help. Together, such biased signaling by particulate Ag promotes MYC expression and reduces the threshold required for B cell proliferation relative to soluble Ag. These findings uncover a molecular basis for highly sensitive B cell response to viral Ag display and remarkable potency of virus-like particle vaccines that is not merely accounted for by avidity and BCR cross-linking, and is independent of the contribution of B cell nucleic acid-sensing machinery.
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15
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Ferapontov A, Omer M, Baudrexel I, Nielsen JS, Dupont DM, Juul-Madsen K, Steen P, Eklund AS, Thiel S, Vorup-Jensen T, Jungmann R, Kjems J, Degn SE. Antigen footprint governs activation of the B cell receptor. Nat Commun 2023; 14:976. [PMID: 36813795 PMCID: PMC9947222 DOI: 10.1038/s41467-023-36672-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Accepted: 02/10/2023] [Indexed: 02/24/2023] Open
Abstract
Antigen binding by B cell receptors (BCR) on cognate B cells elicits a response that eventually leads to production of antibodies. However, it is unclear what the distribution of BCRs is on the naïve B cell and how antigen binding triggers the first step in BCR signaling. Using DNA-PAINT super-resolution microscopy, we find that most BCRs are present as monomers, dimers, or loosely associated clusters on resting B cells, with a nearest-neighbor inter-Fab distance of 20-30 nm. We leverage a Holliday junction nanoscaffold to engineer monodisperse model antigens with precision-controlled affinity and valency, and find that the antigen exerts agonistic effects on the BCR as a function of increasing affinity and avidity. Monovalent macromolecular antigens can activate the BCR at high concentrations, whereas micromolecular antigens cannot, demonstrating that antigen binding does not directly drive activation. Based on this, we propose a BCR activation model determined by the antigen footprint.
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Affiliation(s)
- Alexey Ferapontov
- Department of Biomedicine, Aarhus University, Aarhus C, Denmark.,Center for Cellular Signal Patterns (CellPAT), Aarhus University, Aarhus C, Denmark
| | - Marjan Omer
- Center for Cellular Signal Patterns (CellPAT), Aarhus University, Aarhus C, Denmark.,Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Aarhus C, Denmark
| | - Isabelle Baudrexel
- Center for Cellular Signal Patterns (CellPAT), Aarhus University, Aarhus C, Denmark.,Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Jesper Sejrup Nielsen
- Center for Cellular Signal Patterns (CellPAT), Aarhus University, Aarhus C, Denmark.,Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Aarhus C, Denmark
| | - Daniel Miotto Dupont
- Center for Cellular Signal Patterns (CellPAT), Aarhus University, Aarhus C, Denmark.,Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Aarhus C, Denmark
| | | | - Philipp Steen
- Max Planck Institute of Biochemistry, Martinsried, Germany.,Faculty of Physics and Center for Nanoscience, Ludwig Maximilian University, Munich, Munich, Germany
| | - Alexandra S Eklund
- Center for Cellular Signal Patterns (CellPAT), Aarhus University, Aarhus C, Denmark.,Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Steffen Thiel
- Department of Biomedicine, Aarhus University, Aarhus C, Denmark.,Center for Cellular Signal Patterns (CellPAT), Aarhus University, Aarhus C, Denmark
| | | | - Ralf Jungmann
- Center for Cellular Signal Patterns (CellPAT), Aarhus University, Aarhus C, Denmark.,Max Planck Institute of Biochemistry, Martinsried, Germany.,Faculty of Physics and Center for Nanoscience, Ludwig Maximilian University, Munich, Munich, Germany
| | - Jørgen Kjems
- Center for Cellular Signal Patterns (CellPAT), Aarhus University, Aarhus C, Denmark.,Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Aarhus C, Denmark
| | - Søren Egedal Degn
- Department of Biomedicine, Aarhus University, Aarhus C, Denmark. .,Center for Cellular Signal Patterns (CellPAT), Aarhus University, Aarhus C, Denmark.
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16
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Saltukoglu D, Özdemir B, Holtmannspötter M, Reski R, Piehler J, Kurre R, Reth M. Plasma membrane topography governs the 3D dynamic localization of IgM B cell antigen receptor clusters. EMBO J 2023; 42:e112030. [PMID: 36594262 PMCID: PMC9929642 DOI: 10.15252/embj.2022112030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Revised: 12/04/2022] [Accepted: 12/06/2022] [Indexed: 01/04/2023] Open
Abstract
B lymphocytes recognize bacterial or viral antigens via different classes of the B cell antigen receptor (BCR). Protrusive structures termed microvilli cover lymphocyte surfaces, and are thought to perform sensory functions in screening antigen-bearing surfaces. Here, we have used lattice light-sheet microscopy in combination with tailored custom-built 4D image analysis to study the cell-surface topography of B cells of the Ramos Burkitt's Lymphoma line and the spatiotemporal organization of the IgM-BCR. Ramos B-cell surfaces were found to form dynamic networks of elevated ridges bridging individual microvilli. A fraction of membrane-localized IgM-BCR was found in clusters, which were mainly associated with the ridges and the microvilli. The dynamic ridge-network organization and the IgM-BCR cluster mobility were linked, and both were controlled by Arp2/3 complex activity. Our results suggest that dynamic topographical features of the cell surface govern the localization and transport of IgM-BCR clusters to facilitate antigen screening by B cells.
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Affiliation(s)
- Deniz Saltukoglu
- Department of Molecular Immunology, Biology III, Faculty of BiologyUniversity of FreiburgFreiburgGermany
- Signaling Research Centers CIBSS and BIOSSUniversity of FreiburgFreiburgGermany
| | - Bugra Özdemir
- Signaling Research Centers CIBSS and BIOSSUniversity of FreiburgFreiburgGermany
- Plant Biotechnology, Faculty of BiologyUniversity of FreiburgFreiburgGermany
- Present address:
Euro‐BioImaging, European Molecular Biology Laboratory (EMBL)HeidelbergGermany
| | - Michael Holtmannspötter
- Department of Biology/Chemistry and Center for Cellular NanoanalyticsOsnabrück UniversityOsnabrückGermany
| | - Ralf Reski
- Signaling Research Centers CIBSS and BIOSSUniversity of FreiburgFreiburgGermany
- Plant Biotechnology, Faculty of BiologyUniversity of FreiburgFreiburgGermany
| | - Jacob Piehler
- Department of Biology/Chemistry and Center for Cellular NanoanalyticsOsnabrück UniversityOsnabrückGermany
| | - Rainer Kurre
- Department of Biology/Chemistry and Center for Cellular NanoanalyticsOsnabrück UniversityOsnabrückGermany
| | - Michael Reth
- Department of Molecular Immunology, Biology III, Faculty of BiologyUniversity of FreiburgFreiburgGermany
- Signaling Research Centers CIBSS and BIOSSUniversity of FreiburgFreiburgGermany
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17
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Dirks J, Andres O, Paul L, Manukjan G, Schulze H, Morbach H. IgD shapes the pre-immune naïve B cell compartment in humans. Front Immunol 2023; 14:1096019. [PMID: 36776874 PMCID: PMC9908586 DOI: 10.3389/fimmu.2023.1096019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Accepted: 01/10/2023] [Indexed: 01/27/2023] Open
Abstract
B cell maturation and immunoglobulin (Ig) repertoire selection are governed by expression of a functional B cell receptor (BCR). Naïve B cells co-express their BCR as IgM and IgD isotype. However, the role of the additionally expressed IgD on naïve B cells is not known. Here we assessed the impact of IgD on naïve B cell maturation and Ig repertoire selection in 8 individuals from 3 different families with heterozygous loss-of-function or loss-of expression mutations in IGHD. Although naïve B cells from these individuals expressed IgM on their surface, the IGHD variant in heterozygous state entailed a chimeric situation by allelic exclusion with almost half of the naïve B cell population lacking surface IgD expression. Flow cytometric analyses revealed a distinct phenotype of IgD-negative naïve B cells with decreased expression of CD19, CD20 and CD21 as well as lower BAFF-R and integrin-β7 expression. IgD-negative B cells were less responsive in vitro after engaging the IgM-BCR, TLR7/9 or CD40 pathway. Additionally, a selective disadvantage of IgD-negative B cells within the T2 transitional and mature naïve B cell compartment as well as reduced frequencies of IgMlo/- B cells within the mature naïve B cell compartment lacking IgD were evident. RNA-Ig-seq of bulk sorted B cell populations showed an altered selection of distinct VH segments in the IgD-negative mature naïve B cell population. We conclude that IgD expression on human naïve B cells is redundant for generation of naïve B cells in general, but further shapes the naive B cell compartment starting from T2 transitional B cells. Our observations suggest an unexpected role of IgD expression to be critical for selection of distinct Ig VH segments into the pre-immune Ig repertoire and for the survival of IgMlo/- naïve B cells known to be enriched in poly-/autoreactive B cell clones.
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Affiliation(s)
- Johannes Dirks
- Pediatric Immunology, Department of Pediatrics, University Hospital Würzburg, Würzburg, Germany
| | - Oliver Andres
- Pediatric Immunology, Department of Pediatrics, University Hospital Würzburg, Würzburg, Germany
| | - Luisa Paul
- Pediatric Immunology, Department of Pediatrics, University Hospital Würzburg, Würzburg, Germany.,Department of Pediatrics I, University Hospital Essen, University of Duisburg Essen, Essen, Germany
| | - Georgi Manukjan
- Institute of Experimental Biomedicine I, University Hospital Würzburg, Würzburg, Germany
| | - Harald Schulze
- Institute of Experimental Biomedicine I, University Hospital Würzburg, Würzburg, Germany
| | - Henner Morbach
- Pediatric Immunology, Department of Pediatrics, University Hospital Würzburg, Würzburg, Germany
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18
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Shelby SA, Shaw TR, Veatch SL. Measuring the Co-Localization and Dynamics of Mobile Proteins in Live Cells Undergoing Signaling Responses. Methods Mol Biol 2023; 2654:1-23. [PMID: 37106172 PMCID: PMC10758997 DOI: 10.1007/978-1-0716-3135-5_1] [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] [Indexed: 04/29/2023]
Abstract
Single molecule imaging in live cells enables the study of protein interactions and dynamics as they participate in signaling processes. When combined with fluorophores that stochastically transition between fluorescent and reversible dark states, as in super-resolution localization imaging, labeled molecules can be visualized in single cells over time. This improvement in sampling enables the study of extended cellular responses at the resolution of single molecule localization. This chapter provides optimized experimental and analytical methods used to quantify protein interactions and dynamics within the membranes of adhered live cells. Importantly, the use of pair-correlation functions resolved in both space and time allows researchers to probe interactions between proteins on biologically relevant distance and timescales, even though fluorescence localization methods typically require long times to assemble well-sampled reconstructed images. We describe an application of this approach to measure protein interactions in B cell receptor signaling and include sample analysis code for post-processing of imaging data. These methods are quantitative, sensitive, and broadly applicable to a range of signaling systems.
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Affiliation(s)
- Sarah A Shelby
- Program in Biophysics, University of Michigan, Ann Arbor, MI, USA
| | - Thomas R Shaw
- Program in Applied Physics, University of Michigan, Ann Arbor, MI, USA
| | - Sarah L Veatch
- Program in Biophysics, University of Michigan, Ann Arbor, MI, USA.
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19
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Old and New Facts and Speculations on the Role of the B Cell Receptor in the Origin of Chronic Lymphocytic Leukemia. Int J Mol Sci 2022; 23:ijms232214249. [PMID: 36430731 PMCID: PMC9693457 DOI: 10.3390/ijms232214249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Revised: 11/09/2022] [Accepted: 11/11/2022] [Indexed: 11/19/2022] Open
Abstract
The engagement of the B cell receptor (BcR) on the surface of leukemic cells represents a key event in chronic lymphocytic leukemia (CLL) since it can lead to the maintenance and expansion of the neoplastic clone. This notion was initially suggested by observations of the CLL BcR repertoire and of correlations existing between certain BcR features and the clinical outcomes of single patients. Based on these observations, tyrosine kinase inhibitors (TKIs), which block BcR signaling, have been introduced in therapy with the aim of inhibiting CLL cell clonal expansion and of controlling the disease. Indeed, the impressive results obtained with these compounds provided further proof of the role of BcR in CLL. In this article, the key steps that led to the determination of the role of BcR are reviewed, including the features of the CLL cell repertoire and the fine mechanisms causing BcR engagement and cell signaling. Furthermore, we discuss the biological effects of the engagement, which can lead to cell survival/proliferation or apoptosis depending on certain intrinsic cell characteristics and on signals that the micro-environment can deliver to the leukemic cells. In addition, consideration is given to alternative mechanisms promoting cell proliferation in the absence of BcR signaling, which can explain in part the incomplete effectiveness of TKI therapies. The role of the BcR in determining clonal evolution and disease progression is also described. Finally, we discuss possible models to explain the selection of a special BcR set during leukemogenesis. The BcR may deliver activation signals to the cells, which lead to their uncontrolled growth, with the possible collaboration of other still-undefined events which are capable of deregulating the normal physiological response of B cells to BcR-delivered stimuli.
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20
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Abstract
Single-pass transmembrane receptors (SPTMRs) represent a diverse group of integral membrane proteins that are involved in many essential cellular processes, including signal transduction, cell adhesion, and transmembrane transport of materials. Dysregulation of the SPTMRs is linked with many human diseases. Despite extensive efforts in past decades, the mechanisms of action of the SPTMRs remain incompletely understood. One major hurdle is the lack of structures of the full-length SPTMRs in different functional states. Such structural information is difficult to obtain by traditional structural biology methods such as X-ray crystallography and nuclear magnetic resonance (NMR). The recent rapid development of single-particle cryo-electron microscopy (cryo-EM) has led to an exponential surge in the number of high-resolution structures of integral membrane proteins, including SPTMRs. Cryo-EM structures of SPTMRs solved in the past few years have tremendously improved our understanding of how SPTMRs function. In this review, we will highlight these progresses in the structural studies of SPTMRs by single-particle cryo-EM, analyze important structural details of each protein involved, and discuss their implications on the underlying mechanisms. Finally, we also briefly discuss remaining challenges and exciting opportunities in the field.
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Affiliation(s)
- Kai Cai
- Departments of Biophysics, University of Texas Southwestern Medical Center, Dallas, Texas 75231, USA
| | - Xuewu Zhang
- Departments of Biophysics, University of Texas Southwestern Medical Center, Dallas, Texas 75231, USA
- Departments of Pharmacology, University of Texas Southwestern Medical Center, Dallas, Texas 75231, USA
- Corresponding Author: Xuewu Zhang, Department of pharmacology, UT Southwestern Medical Center, Dallas, TX 75390, USA;
| | - Xiao-chen Bai
- Departments of Biophysics, University of Texas Southwestern Medical Center, Dallas, Texas 75231, USA
- Departments of Cell Biology, University of Texas Southwestern Medical Center, Dallas, Texas 75231, USA
- Corresponding Author: Xiao-chen Bai, Department of Biophysics, UT Southwestern Medical Center, Dallas, TX 75390, USA;
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21
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Zegallai HM, Abu-El-Rub E, Olayinka-Adefemi F, Cole LK, Sparagna GC, Marshall AJ, Hatch GM. Tafazzin deficiency in mouse mesenchymal stem cells promote reprogramming of activated B lymphocytes toward immunosuppressive phenotypes. FASEB J 2022; 36:e22443. [PMID: 35816277 DOI: 10.1096/fj.202200145r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 05/20/2022] [Accepted: 06/27/2022] [Indexed: 11/11/2022]
Abstract
Barth Syndrome (BTHS) is a rare X-linked genetic disorder caused by mutation in the TAFAZZIN gene. Tafazzin (Taz) deficiency in BTHS patients results in an increased risk of infections. Mesenchymal stem cells (MSCs) are well known for their immune-inhibitory function. We examined how Taz-deficiency in murine MSCs impact their ability to modulate the function of lipopolysaccharide (LPS)-activated wild type (WT) B lymphocytes. MSCs from tafazzin knockdown (TazKD) mice exhibited a reduction in mitochondrial cardiolipin compared to wild type (WT) MSCs. However, mitochondrial bioenergetics and membrane potential were unaltered. In contrast, TazKD MSCs exhibited increased reactive oxygen species generation and increased glycolysis. The increased glycolysis was associated with an elevated proliferation, phosphatidylinositol-3-kinase expression and expression of the immunosuppressive markers indoleamine-2,3-dioxygenase, cytotoxic T-lymphocyte-associated protein 4, interleukin-10, and cluster of differentiation 59 compared to controls. Inhibition of glycolysis with 2-deoxyglucose attenuated the TazKD-mediated increased expression of cytotoxic T-lymphocyte-associated protein 4 and interleukin-10. When co-cultured with LPS-activated WT B cells, TazKD MSCs inhibited B cell proliferation and growth rate and reduced B cell secretion of immunoglobulin M compared to controls. In addition, co-culture of LPS-activated WT B cells with TazKD MSCs promoted B cell differentiation toward interleukin-10 secreting plasma cells and B regulatory cells compared to controls. The results indicate that Taz deficiency in MSCs promote reprogramming of activated B lymphocytes toward immunosuppressive phenotypes.
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Affiliation(s)
- Hana M Zegallai
- Diabetes Research Envisioned and Accomplished in Manitoba (DREAM) Theme, Children's Hospital Research Institute of Manitoba, Department of Pharmacology & Therapeutics, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Ejlal Abu-El-Rub
- Physiology and Pathophysiology, Department of Basic Medical Sciences, Faculty of Medicine, Yarmouk University, Irbid, Jordan.,Physiology and Pathophysiology, Regenerative Medicine, Faculty of Medicine, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Folayemi Olayinka-Adefemi
- Department of Immunology, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Laura K Cole
- Diabetes Research Envisioned and Accomplished in Manitoba (DREAM) Theme, Children's Hospital Research Institute of Manitoba, Department of Pharmacology & Therapeutics, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Genevieve C Sparagna
- Department of Medicine, Division of Cardiology, University of Colorado Anschutz Medical Center, Aurora, Colorado, USA
| | - Aaron J Marshall
- Department of Immunology, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Grant M Hatch
- Diabetes Research Envisioned and Accomplished in Manitoba (DREAM) Theme, Children's Hospital Research Institute of Manitoba, Department of Pharmacology & Therapeutics, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada
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22
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Hossain MA, Anasti K, Watts B, Cronin K, Derking R, Groschel B, Kane AP, Edwards R, Easterhoff D, Zhang J, Rountree W, Ortiz Y, Saunders K, Schief WR, Sanders RW, Verkoczy L, Reth M, Alam SM. B cells expressing IgM B cell receptors of HIV-1 neutralizing antibodies discriminate antigen affinities by sensing binding association rates. Cell Rep 2022; 39:111021. [PMID: 35767950 PMCID: PMC9837990 DOI: 10.1016/j.celrep.2022.111021] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Revised: 05/09/2022] [Accepted: 06/08/2022] [Indexed: 01/17/2023] Open
Abstract
HIV-1 envelope (Env) proteins designed to induce neutralizing antibody responses allow study of the role of affinities (equilibrium dissociation constant [KD]) and kinetic rates (association/dissociation rates) on B cell antigen recognition. It is unclear whether affinity discrimination during B cell activation is based solely on Env protein binding KD and whether B cells discriminate among proteins of similar affinities that bind with different kinetic rates. Here, we use a panel of Env proteins and Ramos B cell lines expressing immunoglobulin M (IgM) B cell receptors (BCRs) with specificity for CD4-binding-site broadly neutralizing antibodies to study the role of antigen binding kinetic rates on both early (proximal/distal signaling) and late events (BCR/antigen internalization) in B cell activation. Our results support a kinetic model for B cell activation in which Env protein affinity discrimination is based not on overall KD but on sensing of association rate and a threshold antigen-BCR half-life.
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Affiliation(s)
- Md. Alamgir Hossain
- Human Vaccine Institute, Duke University, Durham, NC, USA,These authors contributed equally
| | - Kara Anasti
- Human Vaccine Institute, Duke University, Durham, NC, USA,These authors contributed equally
| | - Brian Watts
- Human Vaccine Institute, Duke University, Durham, NC, USA
| | - Kenneth Cronin
- Human Vaccine Institute, Duke University, Durham, NC, USA
| | - Ronald Derking
- Human Vaccine Institute, Duke University, Durham, NC, USA
| | - Bettina Groschel
- Department of Immunology & Microbiology and Consortium for HIV/AIDS Vaccine Development, The Scripps Research Institute, La Jolla, CA, USA,IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, CA, USA
| | | | - R.J. Edwards
- Human Vaccine Institute, Duke University, Durham, NC, USA
| | - David Easterhoff
- Human Vaccine Institute, Duke University, Durham, NC, USA,Present address: Moderna, Inc., Cambridge, MA, USA
| | - Jinsong Zhang
- Applied Biomedical Science Institute, San Diego, CA, USA
| | - Wes Rountree
- Human Vaccine Institute, Duke University, Durham, NC, USA
| | - Yaneth Ortiz
- Department of Molecular Immunology, Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Kevin Saunders
- Human Vaccine Institute, Duke University, Durham, NC, USA
| | - William R. Schief
- Department of Immunology & Microbiology and Consortium for HIV/AIDS Vaccine Development, The Scripps Research Institute, La Jolla, CA, USA,IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, CA, USA
| | - Rogier W. Sanders
- Department of Medical Microbiology, Amsterdam UMC, University of Amsterdam, Amsterdam Infection & Immunity Institute, Amsterdam, the Netherlands
| | | | - Michael Reth
- Signaling Research Centers BIOSS and CIBSS, Freiburg, Germany,Department of Molecular Immunology, Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - S. Munir Alam
- Human Vaccine Institute, Duke University, Durham, NC, USA,Department of Medicine & Pathology, Duke University, Durham, NC, USA,Lead contact,Correspondence:
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23
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Pone EJ, Hernandez-Davies JE, Jan S, Silzel E, Felgner PL, Davies DH. Multimericity Amplifies the Synergy of BCR and TLR4 for B Cell Activation and Antibody Class Switching. Front Immunol 2022; 13:882502. [PMID: 35663959 PMCID: PMC9161726 DOI: 10.3389/fimmu.2022.882502] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Accepted: 04/20/2022] [Indexed: 12/15/2022] Open
Abstract
Sustained signaling through the B cell antigen receptor (BCR) is thought to occur only when antigen(s) crosslink or disperse multiple BCR units, such as by multimeric antigens found on the surfaces of viruses or bacteria. B cell-intrinsic Toll-like receptor (TLR) signaling synergizes with the BCR to induce and shape antibody production, hallmarked by immunoglobulin (Ig) class switch recombination (CSR) of constant heavy chains from IgM/IgD to IgG, IgA or IgE isotypes, and somatic hypermutation (SHM) of variable heavy and light chains. Full B cell differentiation is essential for protective immunity, where class switched high affinity antibodies neutralize present pathogens, memory B cells are held in reserve for future encounters, and activated B cells also serve as semi-professional APCs for T cells. But the rules that fine-tune B cell differentiation remain partially understood, despite their being essential for naturally acquired immunity and for guiding vaccine development. To address this in part, we have developed a cell culture system using splenic B cells from naive mice stimulated with several biotinylated ligands and antibodies crosslinked by streptavidin reagents. In particular, biotinylated lipopolysaccharide (LPS), a Toll-like receptor 4 (TLR4) agonist, and biotinylated anti-IgM were pre-assembled (multimerized) using streptavidin, or immobilized on nanoparticles coated with streptavidin, and used to active B cells in this precisely controlled, high throughput assay. Using B cell proliferation and Ig class switching as metrics for successful B cell activation, we show that the stimuli are both synergistic and dose-dependent. Crucially, the multimerized immunoconjugates are most active over a narrow concentration range. These data suggest that multimericity is an essential requirement for B cell BCR/TLRs ligands, and clarify basic rules for B cell activation. Such studies highlight the importance in determining the choice of single vs multimeric formats of antigen and PAMP agonists during vaccine design and development.
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24
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Damm D, Kostka K, Weingärtner C, Wagner JT, Rojas-Sánchez L, Gensberger-Reigl S, Sokolova V, Überla K, Epple M, Temchura V. Covalent coupling of HIV-1 glycoprotein trimers to biodegradable calcium phosphate nanoparticles via genetically encoded aldehyde-tags. Acta Biomater 2022; 140:586-600. [PMID: 34968725 DOI: 10.1016/j.actbio.2021.12.022] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Revised: 12/14/2021] [Accepted: 12/20/2021] [Indexed: 01/02/2023]
Abstract
The usage of antigen-functionalized nanoparticles has become a major focus in the field of experimental HIV-1 vaccine research during the last decade. Various molecular mechanisms to couple native-like trimers of the HIV-1 envelope protein (Env) onto nanoparticle surfaces have been reported, but many come with disadvantages regarding the coupling efficiency and stability. In this study, a short amino acid sequence ("aldehyde-tag") was introduced at the C-terminus of a conformationally stabilized native-like Env. The post-translational conversion of a tag-associated cysteine to formylglycine creates a site-specific aldehyde group without alteration of the Env antigenicity. This aldehyde group was further utilized for bioconjugation of Env trimers. We demonstrated that the low acidic environment necessary for this bioconjugation is not affecting the trimer conformation. Furthermore, we developed a two-step coupling method for pH-sensitive nanoparticles. To this end, we conjugated aldehyde-tagged Env with Propargyl-PEG3-aminooxy linker (oxime ligation; Step-one) and coupled these conjugates by copper-catalyzed azide-alkyne cycloaddition (Click reaction; Step-two) to calcium phosphate nanoparticles (CaPs) functionalized with terminal azide groups. CaPs displaying orthogonally arranged Env trimers on their surface (o-CaPs) were superior in activation of Env-specific B-cells (in vitro) and induction of Env-specific antibody responses (in vivo) compared to CaPs with Env trimers coupled in a randomly oriented manner. Taken together, we present a reliable method for the site-specific, covalent coupling of HIV-1 Env native-like trimers to the surface of nanoparticle delivery systems. This method can be broadly applied for functionalization of nanoparticle platforms with conformationally stabilized candidate antigens for both vaccination and diagnostic approaches. STATEMENT OF SIGNIFICANCE: During the last decade antigen-functionalized nanoparticles have become a major focus in the field of experimental HIV-1 vaccines. Rational design led to the production of conformationally stabilized HIV-1 envelope protein (Env) trimers - the only target for the humoral immune system. Various molecular mechanisms to couple Env trimers onto nanoparticle surfaces have been reported, but many come with disadvantages regarding the coupling efficiency and stability. In this paper, we describe a highly selective bio-conjugation of Env trimers to the surface of medically relevant calcium phosphate nanoparticles. This method maintains the native-like protein conformation and has a broad potential application in functionalization of nanoparticle platforms with stabilized candidate antigens (including stabilized spike proteins of coronaviruses) for both vaccination and diagnostic approaches.
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Affiliation(s)
- D Damm
- Institute of Clinical and Molecular Virology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nuremberg, Schlossgarten 4, 91054 Erlangen, Germany
| | - K Kostka
- Inorganic Chemistry and Center for Nanointegration Duisburg-Essen (CeNIDE), University of Duisburg-Essen, Universitätsstraße 5-7, 45141 Essen, Germany
| | - C Weingärtner
- Institute of Clinical and Molecular Virology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nuremberg, Schlossgarten 4, 91054 Erlangen, Germany
| | - J T Wagner
- Institute of Clinical and Molecular Virology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nuremberg, Schlossgarten 4, 91054 Erlangen, Germany
| | - L Rojas-Sánchez
- Inorganic Chemistry and Center for Nanointegration Duisburg-Essen (CeNIDE), University of Duisburg-Essen, Universitätsstraße 5-7, 45141 Essen, Germany
| | - S Gensberger-Reigl
- Department of Chemistry and Pharmacy, Friedrich-Alexander University Erlangen-Nuremberg, Nikolaus-Fiebiger-Str. 10, 91058 Erlangen, Germany
| | - V Sokolova
- Inorganic Chemistry and Center for Nanointegration Duisburg-Essen (CeNIDE), University of Duisburg-Essen, Universitätsstraße 5-7, 45141 Essen, Germany
| | - K Überla
- Institute of Clinical and Molecular Virology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nuremberg, Schlossgarten 4, 91054 Erlangen, Germany
| | - M Epple
- Inorganic Chemistry and Center for Nanointegration Duisburg-Essen (CeNIDE), University of Duisburg-Essen, Universitätsstraße 5-7, 45141 Essen, Germany
| | - V Temchura
- Institute of Clinical and Molecular Virology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nuremberg, Schlossgarten 4, 91054 Erlangen, Germany.
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25
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Getahun A. Role of inhibitory signaling in peripheral B cell tolerance*. Immunol Rev 2022; 307:27-42. [PMID: 35128676 PMCID: PMC8986582 DOI: 10.1111/imr.13070] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Accepted: 01/17/2022] [Indexed: 12/16/2022]
Abstract
At least 20% of B cells in the periphery expresses an antigen receptor with a degree of self-reactivity. If activated, these autoreactive B cells pose a risk as they can contribute to the development of autoimmune diseases. To prevent their activation, both B cell-intrinsic and extrinsic tolerance mechanisms are in place in healthy individuals. In this review article, I will focus on B cell-intrinsic mechanisms that prevent the activation of autoreactive B cells in the periphery. I will discuss how inhibitory signaling circuits are established in autoreactive B cells, focusing on the Lyn-SHIP-1-SHP-1 axis, how they contribute to peripheral immune tolerance, and how disruptions of these circuits can contribute to the development of autoimmunity.
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Affiliation(s)
- Andrew Getahun
- Department of Immunology and Microbiology University of Colorado SOM Aurora Colorado USA
- Department of Immunology and Genomic Medicine National Jewish Health Denver Colorado USA
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26
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Zhao Y, Knight CM, Jiang Z, Delgado E, Van Hoven AM, Ghanny S, Zhou Z, Zhou H, Yu H, Hu W, Li H, Li X, Perez-Basterrechea M, Zhao L, Zhao Y, Giangola J, Weinberg R, Mazzone T. Stem Cell Educator therapy in type 1 diabetes: From the bench to clinical trials. Clin Exp Rheumatol 2022; 21:103058. [PMID: 35108619 DOI: 10.1016/j.autrev.2022.103058] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2022] [Accepted: 01/25/2022] [Indexed: 12/11/2022]
Abstract
Type 1 diabetes (T1D) is an autoimmune disease that causes a deficit of pancreatic islet β cells. Millions of individuals worldwide have T1D, and its incidence increases annually. Recent clinical trials have highlighted the limits of conventional immunotherapy in T1D and underscore the need for novel treatments that not only overcome multiple immune dysfunctions, but also help restore islet β-cell function. To address these two key issues, we have developed a unique and novel procedure designated the Stem Cell Educator therapy, based on the immune education by cord-blood-derived multipotent stem cells (CB-SC). Over the last 10 years, this technology has been evaluated through international multi-center clinical studies, which have demonstrated its clinical safety and efficacy in T1D and other autoimmune diseases. Mechanistic studies revealed that Educator therapy could fundamentally correct the autoimmunity and induce immune tolerance through multiple molecular and cellular mechanisms such as the expression of a master transcription factor autoimmune regulator (AIRE) in CB-SC for T-cell modulation, an expression of Galectin-9 on CB-SC to suppress activated B cells, and secretion of CB-SC-derived exosomes to polarize human blood monocytes/macrophages into type 2 macrophages. Educator therapy is the leading immunotherapy to date to safely and efficiently correct autoimmunity and restore β cell function in T1D patients.
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Affiliation(s)
- Yong Zhao
- Throne Biotechnologies, Paramus, NJ 07652, USA.
| | - Colette M Knight
- Hackensack Meridian School of Medicine, Inserra Family Diabetes Institute, Department of Medicine, Hackensack University Medical Center, Hackensack, NJ 07601, USA.
| | - Zhaoshun Jiang
- Department of Endocrinology, The 960th Hospital of the PLA Joint Logistics Support Force, Jinan, Shandong 250031, China.
| | - Elias Delgado
- Department of Endocrinology and Nutrition, Hospital Universitario Central de Asturias (HUCA), Department of Medicine, University of Oviedo, Health Research Institute of the Principality of Asturias (ISPA), Oviedo 33006, Spain.
| | - Anne Marie Van Hoven
- Hackensack Meridian School of Medicine, Inserra Family Diabetes Institute, Department of Medicine, Hackensack University Medical Center, Hackensack, NJ 07601, USA
| | - Steven Ghanny
- Department of Pediatric, Division of Endocrinology and Diabetes, Hackensack University Medical Center, Hackensack, NJ 07601, USA
| | - Zhiguang Zhou
- Department of Metabolism and Endocrinology, National Clinical Research Center for Metabolic Diseases, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410011, China
| | - Huimin Zhou
- Section of Endocrinology, The First Affiliated Hospital of Hebei Medical University, Shijiazhuang, Hebei 050031, China
| | - Haibo Yu
- Department of Metabolism and Endocrinology, National Clinical Research Center for Metabolic Diseases, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410011, China
| | - Wei Hu
- Center for Discovery and Innovation, Hackensack Meridian Health, Nutley, USA
| | - Heng Li
- Section of Neurology, Jinan Central Hospital, Shandong University, Jinan, Shandong 250020, China
| | - Xia Li
- Department of Metabolism and Endocrinology, National Clinical Research Center for Metabolic Diseases, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410011, China
| | - Marcos Perez-Basterrechea
- Unit of Cell Therapy and Regenerative Medicine, Hematology and Hemotherapy, Central University Hospital of Asturias, Health Research Institute of the Principality of Asturias (ISPA), Oviedo 33006, Spain
| | - Laura Zhao
- Throne Biotechnologies, Paramus, NJ 07652, USA
| | - Yeqian Zhao
- Throne Biotechnologies, Paramus, NJ 07652, USA
| | - Joseph Giangola
- Hackensack Meridian School of Medicine, Inserra Family Diabetes Institute, Department of Medicine, Hackensack University Medical Center, Hackensack, NJ 07601, USA
| | - Rona Weinberg
- MPN Laboratory, New York Blood Center, New York, NY 10065, USA
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27
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Amendt T, Jumaa H. Adaptive tolerance: Protection through self-recognition. Bioessays 2022; 44:e2100236. [PMID: 34984705 DOI: 10.1002/bies.202100236] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Revised: 12/11/2021] [Accepted: 12/17/2021] [Indexed: 01/10/2023]
Abstract
The random nature of immunoglobulin gene segment rearrangement inevitably leads to the generation of self-reactive B cells. Avoidance of destructive autoimmune reactions is necessary in order to maintain physiological homeostasis. However, current central and peripheral tolerance concepts fail to explain the massive number of autoantibody-borne autoimmune diseases. Moreover, recent studies have shown that in physiological mouse models autoreactive B cells were neither clonally deleted nor kept in an anergic state, but were instead able to mount autoantibody responses. We propose that activation of autoreactive B cells is induced by polyvalent autoantigen complexes that can occur under physiological conditions. Repeated encounter of autoantigen complexes leads to the production of affinity-matured autoreactive IgM that protects its respective self-targets from degradation. We refer to this novel mechanism as adaptive tolerance. This article discusses the discovery of adaptive tolerance and the unexpected role of high affinity IgM autoantibodies.
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Affiliation(s)
- Timm Amendt
- Institute of Immunology, University Hospital Ulm, Ulm, Germany
| | - Hassan Jumaa
- Institute of Immunology, University Hospital Ulm, Ulm, Germany
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28
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Johanson TM, Keenan CR, Allan RS. Shedding Structured Light on Molecular Immunity: The Past, Present and Future of Immune Cell Super Resolution Microscopy. Front Immunol 2021; 12:754200. [PMID: 34975842 PMCID: PMC8715013 DOI: 10.3389/fimmu.2021.754200] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Accepted: 11/23/2021] [Indexed: 12/16/2022] Open
Abstract
In the two decades since the invention of laser-based super resolution microscopy this family of technologies has revolutionised the way life is viewed and understood. Its unparalleled resolution, speed, and accessibility makes super resolution imaging particularly useful in examining the highly complex and dynamic immune system. Here we introduce the super resolution technologies and studies that have already fundamentally changed our understanding of a number of central immunological processes and highlight other immunological puzzles only addressable in super resolution.
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Affiliation(s)
- Timothy M. Johanson
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
- Department of Medical Biology, The University of Melbourne, Parkville, VIC, Australia
| | - Christine R. Keenan
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
- Department of Medical Biology, The University of Melbourne, Parkville, VIC, Australia
| | - Rhys S. Allan
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
- Department of Medical Biology, The University of Melbourne, Parkville, VIC, Australia
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29
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Mazzarello AN, Gentner-Göbel E, Dühren-von Minden M, Tarasenko TN, Nicolò A, Ferrer G, Vergani S, Liu Y, Bagnara D, Rai KR, Burger JA, McGuire PJ, Maity PC, Jumaa H, Chiorazzi N. B-cell receptor isotypes differentially associate with cell signaling, kinetics, and outcome in chronic lymphocytic leukemia. J Clin Invest 2021; 132:149308. [PMID: 34813501 PMCID: PMC8759784 DOI: 10.1172/jci149308] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Accepted: 11/17/2021] [Indexed: 11/17/2022] Open
Abstract
In chronic lymphocytic leukemia (CLL), the B cell receptor (BCR) plays a critical role in disease development and progression, as indicated by the therapeutic efficacy of drugs blocking BCR signaling. However, the mechanism(s) underlying BCR responsiveness are not completely defined. Selective engagement of membrane IgM or IgD on CLL cells, each coexpressed by more than 90% of cases, leads to distinct signaling events. Since both IgM and IgD carry the same antigen-binding domains, the divergent actions of the receptors are attributed to differences in immunoglobulin (Ig) structure or the outcome of signal transduction. We showed that IgM, not IgD, level and organization associated with CLL-cell birth rate and the type and consequences of BCR signaling in humans and mice. The latter IgM-driven effects were abrogated when BCR signaling was inhibited. Collectively, these studies demonstrated a critical, selective role for IgM in BCR signaling and B cell fate decisions, possibly opening new avenues for CLL therapy.
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Affiliation(s)
- Andrea N Mazzarello
- Karches Center for Oncology Research, The Feinstein Institute for Medical Research, Manhasset, United States of America
| | | | | | - Tatyana N Tarasenko
- Metabolism, Infection and Immunity Section, National Institutes of Health, Bethesda, United States of America
| | | | - Gerardo Ferrer
- Karches Center for Oncology Research, The Feinstein Institute for Medical Research, Manhasset, United States of America
| | - Stefano Vergani
- Karches Center for Oncology Research, The Feinstein Institute for Medical Research, Manhasset, United States of America
| | - Yun Liu
- Karches Center for Oncology Research, The Feinstein Institute for Medical Research, Manhasset, United States of America
| | - Davide Bagnara
- Karches Center for Oncology Research, The Feinstein Institute for Medical Research, Manhasset, United States of America
| | - Kanti R Rai
- Karches Center for Oncology Research, The Feinstein Institute for Medical Research, Manhasset, United States of America
| | - Jan A Burger
- Department of Leukemia, University of Texas MD Anderson Cancer Center, Houston, United States of America
| | - Peter J McGuire
- National Institutes of Health, Bethesda, United States of America
| | - Palash C Maity
- Institute for Immunology, University Hospital Ulm, Ulm, Germany
| | - Hassan Jumaa
- Institute for Immunology, University Hospital Ulm, Ulm, Germany
| | - Nicholas Chiorazzi
- Karches Center for Oncology Research, The Feinstein Institute for Medical Research, Manhasset, United States of America
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30
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Wan Z, Zhao Y, Sun Y. Immunoglobulin D and its encoding genes: An updated review. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2021; 124:104198. [PMID: 34237381 DOI: 10.1016/j.dci.2021.104198] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Revised: 04/03/2021] [Accepted: 06/30/2021] [Indexed: 06/13/2023]
Abstract
Since the identification of a functional Cδ gene in ostriches, immunoglobulin (Ig) D has been considered to be an extremely evolutionarily conserved Ig isotype besides the IgM found in all classes of jawed vertebrates. However, in contrast to IgM (which remains stable over evolutionary time), IgD shows considerable structural plasticity among vertebrate species and, moreover, its functions are far from elucidated even in humans and mice. Recently, several studies have shown that high expression of the IgD-B-cell receptor (IgD-BCR) may help physiologically autoreactive B cells survive in peripheral lymphoid tissues thanks to unresponsiveness to self-antigens and help their entry into germinal centers to "redeem" autoreactivity via somatic hypermutation. Other studies have demonstrated that secreted IgD may enhance mucosal homeostasis and immunity by linking B cells with basophils to optimize T-helper-2 cell-mediated responses and to constrain IgE-mediated basophil degranulation. Herein, we review the new discoveries on IgD-encoding genes in jawed vertebrates in the past decade. We also highlight advances in the functions of the IgD-BCR and secreted IgD in humans and mice.
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Affiliation(s)
- Zihui Wan
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, National Engineering Laboratory for Animal Breeding, China Agricultural University, Beijing 100193, People's Republic of China
| | - Yaofeng Zhao
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, National Engineering Laboratory for Animal Breeding, China Agricultural University, Beijing 100193, People's Republic of China
| | - Yi Sun
- Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, College of Animal Science and Veterinary Medicine, Shandong Agricultural University, Tai'an 271018, Shandong, People's Republic of China.
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31
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Zegallai HM, Abu-El-Rub E, Olayinka-Adefemi F, Cole LK, Sparagna GC, Marshall AJ, Hatch GM. Tafazzin deficiency in mouse mesenchymal stem cells potentiates their immunosuppression and impairs activated B lymphocyte immune function. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2021. [PMID: 34729562 DOI: 10.1101/2021.09.07.459330] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Barth Syndrome (BTHS) is a rare X-linked genetic disorder caused by mutation in the TAFAZZIN gene which encodes the cardiolipin (CL) transacylase tafazzin (Taz). Taz deficiency in BTHS patients results in reduced CL in their tissues and a neutropenia which contributes to the risk of infections. However, the impact of Taz deficiency in other cells of the immune system is poorly understood. Mesenchymal stem cells (MSCs) are well known for their immune inhibitory function. We examined whether Taz-deficiency in murine MSCs impacted their ability to modulate lipopolysaccharide (LPS)-activated wild type (WT) murine B lymphocytes. MSCs from tafazzin knockdown (TazKD) mice exhibited a 50% reduction in CL compared to wild type (WT) MSCs. However, mitochondrial oxygen consumption rate and membrane potential were unaltered. In contrast, TazKD MSCs exhibited increased glycolysis compared to WT MSCs and this was associated with elevated proliferation, phosphatidylinositol-3-kinase expression and expression of the immunosuppressive markers indoleamine-2,3-dioxygenase, cytotoxic T-lymphocyte-associated protein 4, interleukin-10, and cluster of differentiation 59. When co-cultured with LPS-activated WT B cells, TazKD MSCs inhibited B cell proliferation and growth rate and reduced B cell secretion of IgM to a greater extent than B cells co-cultured with WT MSCs. In addition, co-culture of LPS-activated WT B cells with TazKD MSCs induced B cell differentiation toward potent immunosuppressive phenotypes including interleukin-10 secreting plasma cells and B regulatory cells compared to activated B cells co-cultured with WT MSCs. These results indicate that Taz deficiency in MSCs enhances MSCs-mediated immunosuppression of activated B lymphocytes.
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32
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Amendt T, Ayoubi OE, Linder AT, Allies G, Young M, Setz CS, Jumaa H. Primary Immune Responses and Affinity Maturation Are Controlled by IgD. Front Immunol 2021; 12:709240. [PMID: 34434193 PMCID: PMC8381280 DOI: 10.3389/fimmu.2021.709240] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Accepted: 07/15/2021] [Indexed: 01/17/2023] Open
Abstract
Mature B cells co-express IgM and IgD B cell antigen receptors (BCR) on their surface. While IgM BCR expression is already essential at early stages of development, the role of the IgD-class BCR remains unclear as most B cell functions appeared unchanged in IgD-deficient mice. Here, we show that IgD-deficient mice have an accelerated rate of B cell responsiveness as they activate antibody production within 24h after immunization, whereas wildtype (WT) animals required 3 days to activate primary antibody responses. Strikingly, soluble monovalent antigen suppresses IgG antibody production induced by multivalent antigen in WT mice. In contrast, IgD-deficient mice were not able to modulate IgG responses suggesting that IgD controls the activation rate of B cells and subsequent antibody production by sensing and distinguishing antigen-valences. Using an insulin-derived peptide we tested the role of IgD in autoimmunity. We show that primary autoreactive antibody responses are generated in WT and in IgD-deficient mice. However, insulin-specific autoantibodies were detected earlier and caused more severe symptoms of autoimmune diabetes in IgD-deficient mice as compared to WT mice. The rapid control of autoimmune diabetes in WT animals was associated with the generation of high-affinity IgM that protects insulin from autoimmune degradation. In IgD-deficient mice, however, the generation of high-affinity protective IgM is delayed resulting in prolonged autoimmune diabetes. Our data suggest that IgD is required for the transition from primary, highly autoreactive, to secondary antigen-specific antibody responses generated by affinity maturation.
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Affiliation(s)
| | | | | | | | | | | | - Hassan Jumaa
- Institute of Immunology, Ulm University Medical Center, Ulm, Germany
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33
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Glowacki SK, Gomes de Castro MA, Yip KM, Asadpour O, Münchhalfen M, Engels N, Opazo F. A fluorescent probe for STED microscopy to study NIP-specific B cells. Analyst 2021; 146:4744-4747. [PMID: 34226908 DOI: 10.1039/d1an00601k] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We have developed a series of monovalent fluorophore-conjugated affinity probes based on the hapten 3-nitro-4-hydroxy-5-iodophenylacetyl (NIP), which is widely used as a model antigen to study B lymphocytes and the functional principles of B cell antigen receptors (BCRs). We successfully used them in flow-cytometry, confocal and super-resolution microscopy techniques.
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Affiliation(s)
- Selda Kabatas Glowacki
- Institute of Neuro- and Sensory Physiology, University Medical Center Göttingen, 37073, Göttingen, Germany
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Abstract
Worldwide about one million patients are given anti-CD20 antibodies such as rituximab (RTX) for the treatment of B cell-associated diseases. Despite the success of this first therapeutic antibody, little is known about the function of its target. The role of CD20 only becomes clear in the context of the nanoscale compartmentalization of the B lymphocyte membrane. We found that CD20 is an organizer of the IgD-class nanocluster on the B cell membrane. The loss of CD20 on human B cells results in a dissolution of the IgD-class nanocluster and a transient B cell activation inducing a B cell-to-PC differentiation. Thus, CD20 is an essential gatekeeper of a membrane nanodomain and the resting state of naive B cells. CD20 is a B cell-specific membrane protein and represents an attractive target for therapeutic antibodies. Despite widespread usage of anti-CD20 antibodies for B cell depletion therapies, the biological function of their target remains unclear. Here, we demonstrate that CD20 controls the nanoscale organization of receptors on the surface of resting B lymphocytes. CRISPR/Cas9-mediated ablation of CD20 in resting B cells resulted in relocalization and interaction of the IgM-class B cell antigen receptor with the coreceptor CD19. This receptor rearrangement led to a transient activation of B cells, accompanied by the internalization of many B cell surface marker proteins. Reexpression of CD20 restored the expression of the B cell surface proteins and the resting state of Ramos B cells. Similarly, treatment of Ramos or naive human B cells with the anti-CD20 antibody rituximab induced nanoscale receptor rearrangements and transient B cell activation in vitro and in vivo. A departure from the resting B cell state followed by the loss of B cell identity of CD20-deficient Ramos B cells was accompanied by a PAX5 to BLIMP-1 transcriptional switch, metabolic reprogramming toward oxidative phosphorylation, and a shift toward plasma cell development. Thus, anti-CD20 engagement or the loss of CD20 disrupts membrane organization, profoundly altering the fate of human B cells.
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Mincham KT, Young JD, Strickland DH. OMIP 076: High-dimensional immunophenotyping of murine T-cell, B-cell, and antibody secreting cell subsets. Cytometry A 2021; 99:888-892. [PMID: 34159723 PMCID: PMC9546025 DOI: 10.1002/cyto.a.24474] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 03/14/2021] [Accepted: 05/31/2021] [Indexed: 11/21/2022]
Affiliation(s)
- Kyle T Mincham
- Telethon Kids Institute, University of Western Australia, Nedlands, Western Australia, Australia
| | - Jacob D Young
- Telethon Kids Institute, University of Western Australia, Nedlands, Western Australia, Australia
| | - Deborah H Strickland
- Telethon Kids Institute, University of Western Australia, Nedlands, Western Australia, Australia
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Bhanja A, Rey-Suarez I, Song W, Upadhyaya A. Bidirectional feedback between BCR signaling and actin cytoskeletal dynamics. FEBS J 2021; 289:4430-4446. [PMID: 34124846 PMCID: PMC8669062 DOI: 10.1111/febs.16074] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2021] [Revised: 05/24/2021] [Accepted: 06/14/2021] [Indexed: 11/30/2022]
Abstract
When B cells are exposed to antigens, they use their B-cell receptors (BCRs) to transduce this external signal into internal signaling cascades and uptake antigen, which activate transcriptional programs. Signaling activation requires complex cytoskeletal remodeling initiated by BCR signaling. The actin cytoskeletal remodeling drives B-cell morphological changes, such as spreading, protrusion, contraction, and endocytosis of antigen by mechanical forces, which in turn affect BCR signaling. Therefore, the relationship between the actin cytoskeleton and BCR signaling is a two-way feedback loop. These morphological changes represent the indirect ways by which the actin cytoskeleton regulates BCR signaling. Recent studies using high spatiotemporal resolution microscopy techniques have revealed that actin also can directly influence BCR signaling. Cortical actin networks directly affect BCR mobility, not only during the resting stage by serving as diffusion barriers, but also at the activation stage by altering BCR diffusivity through enhanced actin flow velocities. Furthermore, the actin cytoskeleton, along with myosin, enables B cells to sense the physical properties of its environment and generate and transmit forces through the BCR. Consequently, the actin cytoskeleton modulates the signaling threshold of BCR to antigenic stimulation. This review discusses the latest research on the relationship between BCR signaling and actin remodeling, and the research techniques. Exploration of the role of actin in BCR signaling will expand fundamental understanding of the relationship between cell signaling and the cytoskeleton and the mechanisms underlying cytoskeleton-related immune disorders and cancer.
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Affiliation(s)
- Anshuman Bhanja
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD, USA
| | - Ivan Rey-Suarez
- Institute for Physical Science and Technology, University of Maryland, College Park, MD, USA
| | - Wenxia Song
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD, USA
| | - Arpita Upadhyaya
- Institute for Physical Science and Technology, University of Maryland, College Park, MD, USA.,Department Physics, University of Maryland, College Park, MD, USA
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Lainšček D, Fink T, Forstnerič V, Hafner-Bratkovič I, Orehek S, Strmšek Ž, Manček-Keber M, Pečan P, Esih H, Malenšek Š, Aupič J, Dekleva P, Plaper T, Vidmar S, Kadunc L, Benčina M, Omersa N, Anderluh G, Pojer F, Lau K, Hacker D, Correia BE, Peterhoff D, Wagner R, Bergant V, Herrmann A, Pichlmair A, Jerala R. A Nanoscaffolded Spike-RBD Vaccine Provides Protection against SARS-CoV-2 with Minimal Anti-Scaffold Response. Vaccines (Basel) 2021; 9:vaccines9050431. [PMID: 33925446 PMCID: PMC8146944 DOI: 10.3390/vaccines9050431] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Revised: 04/22/2021] [Accepted: 04/25/2021] [Indexed: 02/06/2023] Open
Abstract
The response of the adaptive immune system is augmented by multimeric presentation of a specific antigen, resembling viral particles. Several vaccines have been designed based on natural or designed protein scaffolds, which exhibited a potent adaptive immune response to antigens; however, antibodies are also generated against the scaffold, which may impair subsequent vaccination. In order to compare polypeptide scaffolds of different size and oligomerization state with respect to their efficiency, including anti-scaffold immunity, we compared several strategies of presentation of the RBD domain of the SARS-CoV-2 spike protein, an antigen aiming to generate neutralizing antibodies. A comparison of several genetic fusions of RBD to different nanoscaffolding domains (foldon, ferritin, lumazine synthase, and β-annulus peptide) delivered as DNA plasmids demonstrated a strongly augmented immune response, with high titers of neutralizing antibodies and a robust T-cell response in mice. Antibody titers and virus neutralization were most potently enhanced by fusion to the small β-annulus peptide scaffold, which itself triggered a minimal response in contrast to larger scaffolds. The β-annulus fused RBD protein increased residence in lymph nodes and triggered the most potent viral neutralization in immunization by a recombinant protein. Results of the study support the use of a nanoscaffolding platform using the β-annulus peptide for vaccine design.
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Affiliation(s)
- Duško Lainšček
- EN-FIST, Centre of Excellence, 1000 Ljubljana, Slovenia; (D.L.); (I.H.-B.); (M.M.-K.); (M.B.)
- Department of Synthetic Biology and Immunology, National Institute of Chemistry, 1000 Ljubljana, Slovenia; (T.F.); (V.F.); (S.O.); (Ž.S.); (P.P.); (H.E.); (Š.M.); (J.A.); (P.D.); (T.P.); (S.V.); (L.K.)
| | - Tina Fink
- Department of Synthetic Biology and Immunology, National Institute of Chemistry, 1000 Ljubljana, Slovenia; (T.F.); (V.F.); (S.O.); (Ž.S.); (P.P.); (H.E.); (Š.M.); (J.A.); (P.D.); (T.P.); (S.V.); (L.K.)
| | - Vida Forstnerič
- Department of Synthetic Biology and Immunology, National Institute of Chemistry, 1000 Ljubljana, Slovenia; (T.F.); (V.F.); (S.O.); (Ž.S.); (P.P.); (H.E.); (Š.M.); (J.A.); (P.D.); (T.P.); (S.V.); (L.K.)
| | - Iva Hafner-Bratkovič
- EN-FIST, Centre of Excellence, 1000 Ljubljana, Slovenia; (D.L.); (I.H.-B.); (M.M.-K.); (M.B.)
- Department of Synthetic Biology and Immunology, National Institute of Chemistry, 1000 Ljubljana, Slovenia; (T.F.); (V.F.); (S.O.); (Ž.S.); (P.P.); (H.E.); (Š.M.); (J.A.); (P.D.); (T.P.); (S.V.); (L.K.)
| | - Sara Orehek
- Department of Synthetic Biology and Immunology, National Institute of Chemistry, 1000 Ljubljana, Slovenia; (T.F.); (V.F.); (S.O.); (Ž.S.); (P.P.); (H.E.); (Š.M.); (J.A.); (P.D.); (T.P.); (S.V.); (L.K.)
- Graduate School of Biomedicine, University of Ljubljana, 1000 Ljubljana, Slovenia
| | - Žiga Strmšek
- Department of Synthetic Biology and Immunology, National Institute of Chemistry, 1000 Ljubljana, Slovenia; (T.F.); (V.F.); (S.O.); (Ž.S.); (P.P.); (H.E.); (Š.M.); (J.A.); (P.D.); (T.P.); (S.V.); (L.K.)
- Graduate School of Biomedicine, University of Ljubljana, 1000 Ljubljana, Slovenia
| | - Mateja Manček-Keber
- EN-FIST, Centre of Excellence, 1000 Ljubljana, Slovenia; (D.L.); (I.H.-B.); (M.M.-K.); (M.B.)
- Department of Synthetic Biology and Immunology, National Institute of Chemistry, 1000 Ljubljana, Slovenia; (T.F.); (V.F.); (S.O.); (Ž.S.); (P.P.); (H.E.); (Š.M.); (J.A.); (P.D.); (T.P.); (S.V.); (L.K.)
| | - Peter Pečan
- Department of Synthetic Biology and Immunology, National Institute of Chemistry, 1000 Ljubljana, Slovenia; (T.F.); (V.F.); (S.O.); (Ž.S.); (P.P.); (H.E.); (Š.M.); (J.A.); (P.D.); (T.P.); (S.V.); (L.K.)
- Graduate School of Biomedicine, University of Ljubljana, 1000 Ljubljana, Slovenia
| | - Hana Esih
- Department of Synthetic Biology and Immunology, National Institute of Chemistry, 1000 Ljubljana, Slovenia; (T.F.); (V.F.); (S.O.); (Ž.S.); (P.P.); (H.E.); (Š.M.); (J.A.); (P.D.); (T.P.); (S.V.); (L.K.)
- Graduate School of Biomedicine, University of Ljubljana, 1000 Ljubljana, Slovenia
| | - Špela Malenšek
- Department of Synthetic Biology and Immunology, National Institute of Chemistry, 1000 Ljubljana, Slovenia; (T.F.); (V.F.); (S.O.); (Ž.S.); (P.P.); (H.E.); (Š.M.); (J.A.); (P.D.); (T.P.); (S.V.); (L.K.)
- Graduate School of Biomedicine, University of Ljubljana, 1000 Ljubljana, Slovenia
| | - Jana Aupič
- Department of Synthetic Biology and Immunology, National Institute of Chemistry, 1000 Ljubljana, Slovenia; (T.F.); (V.F.); (S.O.); (Ž.S.); (P.P.); (H.E.); (Š.M.); (J.A.); (P.D.); (T.P.); (S.V.); (L.K.)
| | - Petra Dekleva
- Department of Synthetic Biology and Immunology, National Institute of Chemistry, 1000 Ljubljana, Slovenia; (T.F.); (V.F.); (S.O.); (Ž.S.); (P.P.); (H.E.); (Š.M.); (J.A.); (P.D.); (T.P.); (S.V.); (L.K.)
- Graduate School of Biomedicine, University of Ljubljana, 1000 Ljubljana, Slovenia
| | - Tjaša Plaper
- Department of Synthetic Biology and Immunology, National Institute of Chemistry, 1000 Ljubljana, Slovenia; (T.F.); (V.F.); (S.O.); (Ž.S.); (P.P.); (H.E.); (Š.M.); (J.A.); (P.D.); (T.P.); (S.V.); (L.K.)
- Graduate School of Biomedicine, University of Ljubljana, 1000 Ljubljana, Slovenia
| | - Sara Vidmar
- Department of Synthetic Biology and Immunology, National Institute of Chemistry, 1000 Ljubljana, Slovenia; (T.F.); (V.F.); (S.O.); (Ž.S.); (P.P.); (H.E.); (Š.M.); (J.A.); (P.D.); (T.P.); (S.V.); (L.K.)
- Graduate School of Biomedicine, University of Ljubljana, 1000 Ljubljana, Slovenia
| | - Lucija Kadunc
- Department of Synthetic Biology and Immunology, National Institute of Chemistry, 1000 Ljubljana, Slovenia; (T.F.); (V.F.); (S.O.); (Ž.S.); (P.P.); (H.E.); (Š.M.); (J.A.); (P.D.); (T.P.); (S.V.); (L.K.)
| | - Mojca Benčina
- EN-FIST, Centre of Excellence, 1000 Ljubljana, Slovenia; (D.L.); (I.H.-B.); (M.M.-K.); (M.B.)
- Department of Synthetic Biology and Immunology, National Institute of Chemistry, 1000 Ljubljana, Slovenia; (T.F.); (V.F.); (S.O.); (Ž.S.); (P.P.); (H.E.); (Š.M.); (J.A.); (P.D.); (T.P.); (S.V.); (L.K.)
| | - Neža Omersa
- Department of Molecular Biology and Nanobiotechnology, National Institute of Chemistry, 1000 Ljubljana, Slovenia; (N.O.); (G.A.)
| | - Gregor Anderluh
- Department of Molecular Biology and Nanobiotechnology, National Institute of Chemistry, 1000 Ljubljana, Slovenia; (N.O.); (G.A.)
| | - Florence Pojer
- Protein Production and Structure Core Facility PTPSP- EPFL SV PTECH PTPSP, 1015 Lausanne, Switzerland; (F.P.); (K.L.); (D.H.); (B.E.C.)
| | - Kelvin Lau
- Protein Production and Structure Core Facility PTPSP- EPFL SV PTECH PTPSP, 1015 Lausanne, Switzerland; (F.P.); (K.L.); (D.H.); (B.E.C.)
| | - David Hacker
- Protein Production and Structure Core Facility PTPSP- EPFL SV PTECH PTPSP, 1015 Lausanne, Switzerland; (F.P.); (K.L.); (D.H.); (B.E.C.)
| | - Bruno E. Correia
- Protein Production and Structure Core Facility PTPSP- EPFL SV PTECH PTPSP, 1015 Lausanne, Switzerland; (F.P.); (K.L.); (D.H.); (B.E.C.)
| | - David Peterhoff
- Molecular Microbiology (Virology), Institute of Medical Microbiology and Hygiene, University of Regensburg, 93053 Regensburg, Germany; (D.P.); (R.W.)
| | - Ralf Wagner
- Molecular Microbiology (Virology), Institute of Medical Microbiology and Hygiene, University of Regensburg, 93053 Regensburg, Germany; (D.P.); (R.W.)
- Institute of Clinical Microbiology and Hygiene, University Hospital Regensburg, 93053 Regensburg, Germany
| | - Valter Bergant
- Immunopathology of Virus Infections Laboratory, Institute of Virology, Technical University of Munich, 81675 Munich, Germany; (V.B.); (A.H.); (A.P.)
| | - Alexander Herrmann
- Immunopathology of Virus Infections Laboratory, Institute of Virology, Technical University of Munich, 81675 Munich, Germany; (V.B.); (A.H.); (A.P.)
| | - Andreas Pichlmair
- Immunopathology of Virus Infections Laboratory, Institute of Virology, Technical University of Munich, 81675 Munich, Germany; (V.B.); (A.H.); (A.P.)
- German Center for Infection Research (DZIF), Munich Partner Site, 38124 Braunschweig, Germany
| | - Roman Jerala
- EN-FIST, Centre of Excellence, 1000 Ljubljana, Slovenia; (D.L.); (I.H.-B.); (M.M.-K.); (M.B.)
- Department of Synthetic Biology and Immunology, National Institute of Chemistry, 1000 Ljubljana, Slovenia; (T.F.); (V.F.); (S.O.); (Ž.S.); (P.P.); (H.E.); (Š.M.); (J.A.); (P.D.); (T.P.); (S.V.); (L.K.)
- Correspondence:
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38
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Zhang T, Hu W, Chen W. Plasma Membrane Integrates Biophysical and Biochemical Regulation to Trigger Immune Receptor Functions. Front Immunol 2021; 12:613185. [PMID: 33679752 PMCID: PMC7933204 DOI: 10.3389/fimmu.2021.613185] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Accepted: 01/06/2021] [Indexed: 11/23/2022] Open
Abstract
Plasma membrane provides a biophysical and biochemical platform for immune cells to trigger signaling cascades and immune responses against attacks from foreign pathogens or tumor cells. Mounting evidence suggests that the biophysical-chemical properties of this platform, including complex compositions of lipids and cholesterols, membrane tension, and electrical potential, could cooperatively regulate the immune receptor functions. However, the molecular mechanism is still unclear because of the tremendous compositional complexity and spatio-temporal dynamics of the plasma membrane. Here, we review the recent significant progress of dynamical regulation of plasma membrane on immune receptors, including T cell receptor, B cell receptor, Fc receptor, and other important immune receptors, to proceed mechano-chemical sensing and transmembrane signal transduction. We also discuss how biophysical-chemical cues couple together to dynamically tune the receptor's structural conformation or orientation, distribution, and organization, thereby possibly impacting their in-situ ligand binding and related signal transduction. Moreover, we propose that electrical potential could potentially induce the biophysical-chemical coupling change, such as lipid distribution and membrane tension, to inevitably regulate immune receptor activation.
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Affiliation(s)
- Tongtong Zhang
- Department of Hepatobiliary and Pancreatic Surgery, The Center for Integrated Oncology and Precision Medicine, Affiliated Hangzhou First People’s Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Wei Hu
- Department of Cell Biology and Department of Cardiology of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Wei Chen
- Department of Cell Biology and Department of Cardiology of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
- Key Laboratory for Biomedical Engineering of Ministry of Education, State Key Laboratory for Modern Optical Instrumentation, College of Biomedical Engineering and Instrument Science, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Zhejiang University, Hangzhou, China
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Caveolin-1, tetraspanin CD81 and flotillins in lymphocyte cell membrane organization, signaling and immunopathology. Biochem Soc Trans 2020; 48:2387-2397. [PMID: 33242069 DOI: 10.1042/bst20190387] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Revised: 10/08/2020] [Accepted: 10/12/2020] [Indexed: 12/24/2022]
Abstract
The adaptive immune system relies on B and T lymphocytes to ensure a specific and long-lasting protection of an individual from a wide range of potential pathogenic hits. Lymphocytes are highly potent and efficient in eliminating pathogens. However, lymphocyte activation must be tightly regulated to prevent incorrect activity that could result in immunopathologies, such as autoimmune disorders or cancers. Comprehensive insight into the molecular events underlying lymphocyte activation is of enormous importance to better understand the function of the immune system. It provides the basis to design therapeutics to regulate lymphocyte activation in pathological scenarios. Most reported defects in immunopathologies affect the regulation of intracellular signaling pathways. This highlights the importance of these molecules, which control lymphocyte activation and homeostasis impacting lymphocyte tolerance to self, cytokine production and responses to infections. Most evidence for these defects comes from studies of disease models in genetically engineered mice. There is an increasing number of studies focusing on lymphocytes derived from patients which supports these findings. Many indirectly involved proteins are emerging as unexpected regulators of the immune system. In this mini-review, we focus in proteins that regulate plasma membrane (PM) compartmentalization and thereby impact the steady state and the activation of immunoreceptors, namely the T cell antigen receptor (TCR) and the B cell antigen receptor (BCR). Some of these membrane proteins are shown to be involved in immune abnormalities; others, however, are not thoroughly investigated in the context of immune pathogenesis. We aim to highlight them and stimulate future research avenues.
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40
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Wen L, Fan Z, Mikulski Z, Ley K. Imaging of the immune system - towards a subcellular and molecular understanding. J Cell Sci 2020; 133:133/5/jcs234922. [PMID: 32139598 DOI: 10.1242/jcs.234922] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Immune responses involve many types of leukocytes that traffic to the site of injury, recognize the insult and respond appropriately. Imaging of the immune system involves a set of methods and analytical tools that are used to visualize immune responses at the cellular and molecular level as they occur in real time. We will review recent and emerging technological advances in optical imaging, and their application to understanding the molecular and cellular responses of neutrophils, macrophages and lymphocytes. Optical live-cell imaging provides deep mechanistic insights at the molecular, cellular, tissue and organism levels. Live-cell imaging can capture quantitative information in real time at subcellular resolution with minimal phototoxicity and repeatedly in the same living cells or in accessible tissues of the living organism. Advanced FRET probes allow tracking signaling events in live cells. Light-sheet microscopy allows for deeper tissue penetration in optically clear samples, enriching our understanding of the higher-level organization of the immune response. Super-resolution microscopy offers insights into compartmentalized signaling at a resolution beyond the diffraction limit, approaching single-molecule resolution. This Review provides a current perspective on live-cell imaging in vitro and in vivo with a focus on the assessment of the immune system.
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Affiliation(s)
- Lai Wen
- Laboratory of Inflammation Biology, La Jolla Institute for Immunology, 9420 Athena Circle Drive, La Jolla, CA 92037, USA
| | - Zhichao Fan
- Department of Immunology, School of Medicine, UConn Health, 263 Farmington Avenue, Farmington, CT 06030, USA
| | - Zbigniew Mikulski
- Microscopy Core Facility, La Jolla Institute for Immunology, 9420 Athena Circle Drive, La Jolla, CA 92037, USA
| | - Klaus Ley
- Laboratory of Inflammation Biology, La Jolla Institute for Immunology, 9420 Athena Circle Drive, La Jolla, CA 92037, USA .,Department of Bioengineering, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
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Rey-Suarez I, Wheatley BA, Koo P, Bhanja A, Shu Z, Mochrie S, Song W, Shroff H, Upadhyaya A. WASP family proteins regulate the mobility of the B cell receptor during signaling activation. Nat Commun 2020; 11:439. [PMID: 31974357 PMCID: PMC6978525 DOI: 10.1038/s41467-020-14335-8] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Accepted: 12/23/2019] [Indexed: 12/13/2022] Open
Abstract
Regulation of membrane receptor mobility tunes cellular response to external signals, such as in binding of B cell receptors (BCR) to antigen, which initiates signaling. However, whether BCR signaling is regulated by BCR mobility, and what factors mediate this regulation, are not well understood. Here we use single molecule imaging to examine BCR movement during signaling activation and a novel machine learning method to classify BCR trajectories into distinct diffusive states. Inhibition of actin dynamics downstream of the actin nucleating factors, Arp2/3 and formin, decreases BCR mobility. Constitutive loss or acute inhibition of the Arp2/3 regulator, N-WASP, which is associated with enhanced signaling, increases the proportion of BCR trajectories with lower diffusivity. Furthermore, loss of N-WASP reduces the diffusivity of CD19, a stimulatory co-receptor, but not that of FcγRIIB, an inhibitory co-receptor. Our results implicate a dynamic actin network in fine-tuning receptor mobility and receptor-ligand interactions for modulating B cell signaling. B cell receptors (BCR) capture antigen and initiate downstream antibody responses, but whether and how BCR signaling is regulated by BCR mobility is still unclear. Here the authors show, using single molecule imaging and machine learning analyses, that BCR and CD19 mobility is modulated by the actin nucleation regulators Arp2/3 and N-WASP to control BCR signaling.
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Affiliation(s)
- Ivan Rey-Suarez
- Biophysics Program, University of Maryland, College Park, MD, 20742, USA.,National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD, USA
| | - Brittany A Wheatley
- Department of Physics, University of Maryland, College Park, MD, 20742, USA.,Institute for Physical Science and Technology, University of Maryland, College Park, MD, 20742, USA
| | - Peter Koo
- Department of Molecular & Cellular Biology, Harvard University, Cambridge, MA, 02138, USA
| | - Anshuman Bhanja
- Department of Cell Biology & Molecular Genetics, University of Maryland, College Park, MD, 20742, USA
| | - Zhou Shu
- Department of Cell Biology & Molecular Genetics, University of Maryland, College Park, MD, 20742, USA.,Division of Immunology, Children's Hospital of Chongqing Medical University, Chongqing, China
| | - Simon Mochrie
- Department of Physics, Yale University, New Haven, CT, 06520, USA
| | - Wenxia Song
- Department of Cell Biology & Molecular Genetics, University of Maryland, College Park, MD, 20742, USA
| | - Hari Shroff
- National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD, USA
| | - Arpita Upadhyaya
- Biophysics Program, University of Maryland, College Park, MD, 20742, USA. .,Department of Physics, University of Maryland, College Park, MD, 20742, USA. .,Institute for Physical Science and Technology, University of Maryland, College Park, MD, 20742, USA.
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42
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Westerfield JM, Barrera FN. Membrane receptor activation mechanisms and transmembrane peptide tools to elucidate them. J Biol Chem 2019; 295:1792-1814. [PMID: 31879273 DOI: 10.1074/jbc.rev119.009457] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Single-pass membrane receptors contain extracellular domains that respond to external stimuli and transmit information to intracellular domains through a single transmembrane (TM) α-helix. Because membrane receptors have various roles in homeostasis, signaling malfunctions of these receptors can cause disease. Despite their importance, there is still much to be understood mechanistically about how single-pass receptors are activated. In general, single-pass receptors respond to extracellular stimuli via alterations in their oligomeric state. The details of this process are still the focus of intense study, and several lines of evidence indicate that the TM domain (TMD) of the receptor plays a central role. We discuss three major mechanistic hypotheses for receptor activation: ligand-induced dimerization, ligand-induced rotation, and receptor clustering. Recent observations suggest that receptors can use a combination of these activation mechanisms and that technical limitations can bias interpretation. Short peptides derived from receptor TMDs, which can be identified by screening or rationally developed on the basis of the structure or sequence of their targets, have provided critical insights into receptor function. Here, we explore recent evidence that, depending on the target receptor, TMD peptides cannot only inhibit but also activate target receptors and can accommodate novel, bifunctional designs. Furthermore, we call for more sharing of negative results to inform the TMD peptide field, which is rapidly transforming into a suite of unique tools with the potential for future therapeutics.
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Affiliation(s)
- Justin M Westerfield
- Department of Biochemistry & Cellular and Molecular Biology, University of Tennessee, Knoxville, Tennessee 37996
| | - Francisco N Barrera
- Department of Biochemistry & Cellular and Molecular Biology, University of Tennessee, Knoxville, Tennessee 37996.
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43
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Sun Y, Huang T, Hammarström L, Zhao Y. The Immunoglobulins: New Insights, Implications, and Applications. Annu Rev Anim Biosci 2019; 8:145-169. [PMID: 31846352 DOI: 10.1146/annurev-animal-021419-083720] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Immunoglobulins (Igs), as one of the hallmarks of adaptive immunity, first arose approximately 500 million years ago with the emergence of jawed vertebrates. Two events stand out in the evolutionary history of Igs from cartilaginous fish to mammals: (a) the diversification of Ig heavy chain (IgH) genes, resulting in Ig isotypes or subclasses associated with novel functions, and (b) the diversification of genetic and structural strategies, leading to the creation of the antibody repertoire we know today. This review first gives an overview of the IgH isotypes identified in jawed vertebrates to date and then highlights the implications or applications of five new recent discoveries arising from comparative studies of Igs derived from different vertebrate species.
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Affiliation(s)
- Yi Sun
- Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, College of Animal Science and Veterinary Medicine, Shandong Agricultural University, Tai'an 271018, Shandong, People's Republic of China;
| | - Tian Huang
- Henan Engineering Laboratory for Mammary Bioreactor, School of Life Sciences, Henan University, Kaifeng 475004, Henan, People's Republic of China;
| | - Lennart Hammarström
- Division of Clinical Immunology and Transfusion Medicine, Department of Laboratory Medicine, Karolinska Institutet at Karolinska Hospital Huddinge, Karolinska University Hospital Huddinge, SE-141 86 Stockholm, Sweden;
| | - Yaofeng Zhao
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, National Engineering Laboratory for Animal Breeding, China Agricultural University, Beijing 100193, People's Republic of China;
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44
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Zheng S, Sieder M, Mitterer M, Reth M, Cavallari M, Yang J. A new branched proximity hybridization assay for the quantification of nanoscale protein-protein proximity. PLoS Biol 2019; 17:e3000569. [PMID: 31825964 PMCID: PMC6905527 DOI: 10.1371/journal.pbio.3000569] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Accepted: 11/14/2019] [Indexed: 01/15/2023] Open
Abstract
Membrane proteins are organized in nanoscale compartments. Their reorganization plays a crucial role in receptor activation and cell signaling. To monitor the organization and reorganization of membrane proteins, we developed a new branched proximity hybridization assay (bPHA) allowing better quantification of the nanoscale protein-protein proximity. In this assay, oligo-coupled binding probes, such as aptamer, nanobody, and antibodies, are used to translate the proximity of target proteins to the proximity of oligos. The closely positioned oligos then serve as a template for a maximum of 400-fold branched DNA (bDNA) signal amplification. The amplified bPHA signal is recorded by flow cytometer, thus enabling proximity studies with high throughput, multiplexing, and single-cell resolution. To demonstrate the potential of the bPHA method, we measured the reorganization of the immunoglobulin M (IgM)- and immunoglobulin D (IgD)-class B cell antigen receptor (BCR) on the plasma membrane and the recruitment of spleen tyrosine kinase (Syk) to the BCR upon B lymphocyte activation.
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Affiliation(s)
- Shuangshuang Zheng
- BIOSS Centre For Biological Signaling Studies and Department of Molecular Immunology, Biology III, Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Melanie Sieder
- BIOSS Centre For Biological Signaling Studies and Department of Molecular Immunology, Biology III, Faculty of Biology, University of Freiburg, Freiburg, Germany
- Spemann Graduate School for Biology and Medicine (SGBM), Freiburg, Germany
| | - Michael Mitterer
- Max Planck Institute of Immunobiology and Epigenetics, Freiburg, Germany
| | - Michael Reth
- BIOSS Centre For Biological Signaling Studies and Department of Molecular Immunology, Biology III, Faculty of Biology, University of Freiburg, Freiburg, Germany
- Max Planck Institute of Immunobiology and Epigenetics, Freiburg, Germany
| | - Marco Cavallari
- BIOSS Centre For Biological Signaling Studies and Department of Molecular Immunology, Biology III, Faculty of Biology, University of Freiburg, Freiburg, Germany
- Max Planck Institute of Immunobiology and Epigenetics, Freiburg, Germany
| | - Jianying Yang
- BIOSS Centre For Biological Signaling Studies and Department of Molecular Immunology, Biology III, Faculty of Biology, University of Freiburg, Freiburg, Germany
- Max Planck Institute of Immunobiology and Epigenetics, Freiburg, Germany
- * E-mail:
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45
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Tan C, Noviski M, Huizar J, Zikherman J. Self-reactivity on a spectrum: A sliding scale of peripheral B cell tolerance. Immunol Rev 2019; 292:37-60. [PMID: 31631352 DOI: 10.1111/imr.12818] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Accepted: 10/02/2019] [Indexed: 12/16/2022]
Abstract
Efficient mechanisms of central tolerance, including receptor editing and deletion, prevent highly self-reactive B cell receptors (BCRs) from populating the periphery. Despite this, modest self-reactivity persists in (and may even be actively selected into) the mature B cell repertoire. In this review, we discuss new insights into mechanisms of peripheral B cell tolerance that restrain mature B cells from mounting inappropriate responses to endogenous antigens, and place recent work into historical context. In particular, we discuss new findings that have arisen from application of a novel in vivo reporter of BCR signaling, Nur77-eGFP, expression of which scales with the degree of self-reactivity in both monoclonal and polyclonal B cell repertoires. We discuss new and historical evidence that self-reactivity is not just tolerated, but actively selected into the peripheral repertoire. We review recent progress in understanding how dual expression of the IgM and IgD BCR isotypes on mature naive follicular B cells tunes responsiveness to endogenous antigen recognition, and discuss how this may be integrated with other features of clonal anergy. Finally, we discuss how expression of Nur77 itself couples chronic antigen stimulation with B cell tolerance.
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Affiliation(s)
- Corey Tan
- Biomedical Sciences (BMS) Graduate Program, University of California, San Francisco, CA, USA
| | - Mark Noviski
- Biomedical Sciences (BMS) Graduate Program, University of California, San Francisco, CA, USA.,Division of Rheumatology, Department of Medicine, Rosalind Russell and Ephraim P. Engleman Arthritis Research Center, University of California, San Francisco, CA, USA
| | - John Huizar
- School of Medicine, HHMI Medical Fellows Program, University of California, San Francisco, CA, USA
| | - Julie Zikherman
- Division of Rheumatology, Department of Medicine, Rosalind Russell and Ephraim P. Engleman Arthritis Research Center, University of California, San Francisco, CA, USA
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46
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Schwickert TA, Tagoh H, Schindler K, Fischer M, Jaritz M, Busslinger M. Ikaros prevents autoimmunity by controlling anergy and Toll-like receptor signaling in B cells. Nat Immunol 2019; 20:1517-1529. [PMID: 31591571 DOI: 10.1038/s41590-019-0490-2] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2018] [Accepted: 08/06/2019] [Indexed: 12/21/2022]
Abstract
The establishment of a diverse B cell antigen receptor (BCR) repertoire by V(D)J recombination also generates autoreactive B cells. Anergy is one tolerance mechanism; it renders autoreactive B cells insensitive to stimulation by self-antigen, whereas Toll-like receptor (TLR) signaling can reactivate anergic B cells. Here, we describe a critical role of the transcription factor Ikaros in controlling BCR anergy and TLR signaling. Mice with specific deletion of Ikaros in mature B cells developed systemic autoimmunity. Ikaros regulated many anergy-associated genes, including Zfp318, which is implicated in the attenuation of BCR responsiveness by promoting immunoglobulin D expression in anergic B cells. TLR signaling was hyperactive in Ikaros-deficient B cells, which failed to upregulate feedback inhibitors of the MyD88-nuclear factor κB signaling pathway. Systemic inflammation was lost on expression of a non-self-reactive BCR or loss of MyD88 in Ikaros-deficient B cells. Thus, Ikaros acts as a guardian preventing autoimmunity by promoting BCR anergy and restraining TLR signaling.
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Affiliation(s)
- Tanja A Schwickert
- Research Institute of Molecular Pathology, Vienna Biocenter, Vienna, Austria.
| | - Hiromi Tagoh
- Research Institute of Molecular Pathology, Vienna Biocenter, Vienna, Austria.,Ludwig Institute for Cancer Research, University of Oxford, Oxford, UK
| | - Karina Schindler
- Research Institute of Molecular Pathology, Vienna Biocenter, Vienna, Austria
| | - Maria Fischer
- Research Institute of Molecular Pathology, Vienna Biocenter, Vienna, Austria
| | - Markus Jaritz
- Research Institute of Molecular Pathology, Vienna Biocenter, Vienna, Austria
| | - Meinrad Busslinger
- Research Institute of Molecular Pathology, Vienna Biocenter, Vienna, Austria.
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47
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Allard CAH, Opalko HE, Moseley JB. Stable Pom1 clusters form a glucose-modulated concentration gradient that regulates mitotic entry. eLife 2019; 8:e46003. [PMID: 31050341 PMCID: PMC6524964 DOI: 10.7554/elife.46003] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Accepted: 05/02/2019] [Indexed: 12/12/2022] Open
Abstract
Control of cell size requires molecular size sensors that are coupled to the cell cycle. Rod-shaped fission yeast cells divide at a threshold size partly due to Cdr2 kinase, which forms nodes at the medial cell cortex where it inhibits the Cdk1-inhibitor Wee1. Pom1 kinase phosphorylates and inhibits Cdr2, and forms cortical concentration gradients from cell poles. Pom1 inhibits Cdr2 signaling to Wee1 specifically in small cells, but the time and place of their regulatory interactions were unclear. We show that Pom1 forms stable oligomeric clusters that dynamically sample the cell cortex. Binding frequency is patterned into a concentration gradient by the polarity landmarks Tea1 and Tea4. Pom1 clusters colocalize with Cdr2 nodes, forming a glucose-modulated inhibitory threshold against node activation. Our work reveals how Pom1-Cdr2-Wee1 operates in multiprotein clusters at the cortex to promote mitotic entry at a cell size that can be modified by nutrient availability.
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Affiliation(s)
- Corey A H Allard
- Department of Biochemistry and Cell BiologyThe Geisel School of Medicine at DartmouthHanoverUnited States
| | - Hannah E Opalko
- Department of Biochemistry and Cell BiologyThe Geisel School of Medicine at DartmouthHanoverUnited States
| | - James B Moseley
- Department of Biochemistry and Cell BiologyThe Geisel School of Medicine at DartmouthHanoverUnited States
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48
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Gold MR, Reth MG. Antigen Receptor Function in the Context of the Nanoscale Organization of the B Cell Membrane. Annu Rev Immunol 2019; 37:97-123. [DOI: 10.1146/annurev-immunol-042718-041704] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The B cell antigen receptor (BCR) plays a central role in the self/nonself selection of B lymphocytes and in their activation by cognate antigen during the clonal selection process. It was long thought that most cell surface receptors, including the BCR, were freely diffusing and randomly distributed. Since the advent of superresolution techniques, it has become clear that the plasma membrane is compartmentalized and highly organized at the nanometer scale. Hence, a complete understanding of the precise conformation and activation mechanism of the BCR must take into account the organization of the B cell plasma membrane. We review here the recent literature on the nanoscale organization of the lymphocyte membrane and discuss how this new information influences our view of the conformational changes that the BCR undergoes during activation.
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Affiliation(s)
- Michael R. Gold
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
- Life Sciences Institute, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Michael G. Reth
- BIOSS Centre for Biological Signaling Studies, University of Freiburg, 79104 Freiburg, Germany
- Department of Molecular Immunology, Institute of Biology III, Faculty of Biology, University of Freiburg, 79108 Freiburg, Germany
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49
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Wilhelm I, Levit-Zerdoun E, Jakob J, Villringer S, Frensch M, Übelhart R, Landi A, Müller P, Imberty A, Thuenauer R, Claudinon J, Jumaa H, Reth M, Eibel H, Hobeika E, Römer W. Carbohydrate-dependent B cell activation by fucose-binding bacterial lectins. Sci Signal 2019; 12:12/571/eaao7194. [PMID: 30837305 DOI: 10.1126/scisignal.aao7194] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Bacterial lectins are typically multivalent and bind noncovalently to specific carbohydrates on host tissues to facilitate bacterial adhesion. Here, we analyzed the effects of two fucose-binding lectins, BambL from Burkholderia ambifaria and LecB from Pseudomonas aeruginosa, on specific signaling pathways in B cells. We found that these bacterial lectins induced B cell activation, which, in vitro, was dependent on the cell surface expression of the B cell antigen receptor (BCR) and its co-receptor CD19, as well as on spleen tyrosine kinase (Syk) activity. The resulting release of intracellular Ca2+ was followed by an increase in the cell surface abundance of the activation marker CD86, augmented cytokine secretion, and subsequent cell death, replicating all of the events that are observed in vitro upon canonical and antigen-mediated B cell activation. Moreover, injection of BambL in mice resulted in a substantial, BCR-independent loss of B cells in the bone marrow with simultaneous, transient enlargement of the spleen (splenomegaly), as well as an increase in the numbers of splenic B cells and myeloid cells. Together, these data suggest that bacterial lectins can initiate polyclonal activation of B cells through their sole capacity to bind to fucose.
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Affiliation(s)
- Isabel Wilhelm
- Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany.,Spemann Graduate School of Biology and Medicine (SGBM), University of Freiburg, 79104 Freiburg, Germany.,Signalling Research Centres BIOSS and CIBSS, University of Freiburg, 79104 Freiburg, Germany
| | - Ella Levit-Zerdoun
- Max Planck Institute of Immunology and Epigenetics Freiburg, 79108 Freiburg, Germany.,International Max Planck Research School (IMPRS), Max Planck Institute of Immunobiology and Epigenetics Freiburg, 79108 Freiburg, Germany.,German Cancer Consortium (DKTK) partner site Freiburg, German Cancer Center (DKFZ), Heidelberg, Institute of Molecular Medicine and Cell Research, 79104 Freiburg, Germany
| | - Johanna Jakob
- Institute for Immunology, University Medical Centre Ulm, 89081 Ulm, Germany
| | - Sarah Villringer
- Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany.,Signalling Research Centres BIOSS and CIBSS, University of Freiburg, 79104 Freiburg, Germany
| | - Marco Frensch
- Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany.,Signalling Research Centres BIOSS and CIBSS, University of Freiburg, 79104 Freiburg, Germany.,International Max Planck Research School (IMPRS), Max Planck Institute of Immunobiology and Epigenetics Freiburg, 79108 Freiburg, Germany
| | - Rudolf Übelhart
- Institute for Immunology, University Medical Centre Ulm, 89081 Ulm, Germany
| | - Alessia Landi
- Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany.,Signalling Research Centres BIOSS and CIBSS, University of Freiburg, 79104 Freiburg, Germany
| | - Peter Müller
- Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany.,Signalling Research Centres BIOSS and CIBSS, University of Freiburg, 79104 Freiburg, Germany
| | - Anne Imberty
- Univ. Grenoble Alpes, CNRS, CERMAV, 38000 Grenoble, France
| | - Roland Thuenauer
- Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany.,Signalling Research Centres BIOSS and CIBSS, University of Freiburg, 79104 Freiburg, Germany
| | - Julie Claudinon
- Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany.,Signalling Research Centres BIOSS and CIBSS, University of Freiburg, 79104 Freiburg, Germany
| | - Hassan Jumaa
- Institute for Immunology, University Medical Centre Ulm, 89081 Ulm, Germany
| | - Michael Reth
- Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany.,Signalling Research Centres BIOSS and CIBSS, University of Freiburg, 79104 Freiburg, Germany.,Max Planck Institute of Immunology and Epigenetics Freiburg, 79108 Freiburg, Germany
| | - Hermann Eibel
- CCI-Center for Chronic Immunodeficiency (CCI), University Medical Centre, 79106 Freiburg, Germany.,Faculty of Medicine, University of Freiburg, 79106 Freiburg, Germany
| | - Elias Hobeika
- Institute for Immunology, University Medical Centre Ulm, 89081 Ulm, Germany.
| | - Winfried Römer
- Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany. .,Spemann Graduate School of Biology and Medicine (SGBM), University of Freiburg, 79104 Freiburg, Germany.,Signalling Research Centres BIOSS and CIBSS, University of Freiburg, 79104 Freiburg, Germany
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50
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Gomes de Castro MA, Wildhagen H, Sograte-Idrissi S, Hitzing C, Binder M, Trepel M, Engels N, Opazo F. Differential organization of tonic and chronic B cell antigen receptors in the plasma membrane. Nat Commun 2019; 10:820. [PMID: 30778055 PMCID: PMC6379438 DOI: 10.1038/s41467-019-08677-1] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2017] [Accepted: 01/24/2019] [Indexed: 11/09/2022] Open
Abstract
Stimulation of the B cell antigen receptor (BCR) triggers signaling pathways that promote the differentiation of B cells into plasma cells. Despite the pivotal function of BCR in B cell activation, the organization of the BCR on the surface of resting and antigen-activated B cells remains unclear. Here we show, using STED super-resolution microscopy, that IgM-containing BCRs exist predominantly as monomers and dimers in the plasma membrane of resting B cells, but form higher oligomeric clusters upon stimulation. By contrast, a chronic lymphocytic leukemia-derived BCR forms dimers and oligomers in the absence of a stimulus, but a single amino acid exchange reverts its organization to monomers in unstimulated B cells. Our super-resolution microscopy approach for quantitatively analyzing cell surface proteins may thus help reveal the nanoscale organization of immunoreceptors in various cell types.
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MESH Headings
- B-Lymphocytes/metabolism
- Burkitt Lymphoma/pathology
- Cell Line, Tumor
- Cell Membrane/metabolism
- Humans
- Immunoglobulin Fab Fragments/genetics
- Immunoglobulin Fab Fragments/metabolism
- Immunoglobulin M/metabolism
- Leukemia, Lymphocytic, Chronic, B-Cell/metabolism
- Leukemia, Lymphocytic, Chronic, B-Cell/pathology
- Microscopy, Fluorescence/methods
- Protein Multimerization
- Receptors, Antigen, B-Cell/genetics
- Receptors, Antigen, B-Cell/metabolism
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Affiliation(s)
- Maria Angela Gomes de Castro
- Institute of Neuro- and Sensory Physiology, University Medical Center Göttingen, Humboldtallee 23, 37073, Göttingen, Germany
| | - Hanna Wildhagen
- Institute of Neuro- and Sensory Physiology, University Medical Center Göttingen, Humboldtallee 23, 37073, Göttingen, Germany
| | - Shama Sograte-Idrissi
- Institute of Neuro- and Sensory Physiology, University Medical Center Göttingen, Humboldtallee 23, 37073, Göttingen, Germany
- Center for Biostructural Imaging of Neurodegeneration (BIN), University of Göttingen Medical Center, von-Siebold-Straße 3a, 37075, Göttingen, Germany
| | - Christoffer Hitzing
- Institute of Cellular and Molecular Immunology, University Medical Center Göttingen, Humboldtallee 34, 37073, Göttingen, Germany
| | - Mascha Binder
- Department of Oncology and Hematology, BMT with section Pneumology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany
| | - Martin Trepel
- Department of Oncology and Hematology, BMT with section Pneumology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany
- Department of Hematology and Oncology, Augsburg Medical Center, Stenglinstr. 2, 86156, Augsburg, Germany
| | - Niklas Engels
- Institute of Cellular and Molecular Immunology, University Medical Center Göttingen, Humboldtallee 34, 37073, Göttingen, Germany.
| | - Felipe Opazo
- Institute of Neuro- and Sensory Physiology, University Medical Center Göttingen, Humboldtallee 23, 37073, Göttingen, Germany.
- Center for Biostructural Imaging of Neurodegeneration (BIN), University of Göttingen Medical Center, von-Siebold-Straße 3a, 37075, Göttingen, Germany.
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