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Hoh RA, Thörnqvist L, Yang F, Godzwon M, King JJ, Lee JY, Greiff L, Boyd SD, Ohlin M. Clonal evolution and stereotyped sequences of human IgE lineages in aeroallergen-specific immunotherapy. J Allergy Clin Immunol 2023; 152:214-229. [PMID: 36828082 DOI: 10.1016/j.jaci.2023.02.009] [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: 08/02/2022] [Revised: 01/22/2023] [Accepted: 02/09/2023] [Indexed: 02/24/2023]
Abstract
BACKGROUND Allergic disease reflects specific inflammatory processes initiated by interaction between allergen and allergen-specific IgE. Specific immunotherapy (SIT) is an effective long-term treatment option, but the mechanisms by which SIT provides desensitization are not well understood. OBJECTIVE Our aim was to characterize IgE sequences expressed by allergen-specific B cells over a 3-year longitudinal study of patients with aeroallergies who were undergoing SIT. METHODS Allergen-specific IgE-expressing clones were identified by using combinatorial single-chain variable fragment libraries and tracked in PBMCs and nasal biopsy samples over a 3-year period with antibody gene repertoire sequencing. The characteristics of private IgE-expressing clones were compared with those of stereotyped or "public" IgE responses to the grass pollen allergen Phleum pratense (Phl p) 2. RESULT Members of the same allergen-specific IgE lineages were observed in nasal biopsy samples and blood, and lineages detected at baseline persisted in blood and nasal biopsy samples after 3 years of SIT, including B cells that express IgE. Evidence of progressive class switch recombination to IgG subclasses was observed after 3 years of SIT. A common stereotyped Phl p 2-specific antibody heavy chain sequence was detected in multiple donors. The amino acid residues enriched in IgE-stereotyped sequences from seropositive donors were analyzed with machine learning and k-mer motif discovery. Stereotyped IgE sequences had lower overall rates of somatic hypermutation and antigen selection than did single-chain variable fragment-derived allergen-specific sequences or IgE sequences of unknown specificity. CONCLUSION Longitudinal tracking of rare circulating and tissue-resident allergen-specific IgE+ clones demonstrates persistence of allergen-specific IgE+ clones, progressive class switch recombination to IgG subtypes, and distinct maturation of a stereotyped Phl p 2 clonotype.
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Affiliation(s)
- Ramona A Hoh
- Department of Pathology, Stanford University, Stanford, Calif
| | | | - Fan Yang
- Department of Pathology, Stanford University, Stanford, Calif
| | | | - Jasmine J King
- Department of Pathology, Stanford University, Stanford, Calif
| | - Ji-Yeun Lee
- Department of Pathology, Stanford University, Stanford, Calif
| | - Lennart Greiff
- Department of Clinical Sciences, Lund University, Lund, Sweden; Department of Otorhinolaryngology, Head and Neck Surgery, Skåne University Hospital, Lund, Sweden
| | - Scott D Boyd
- Department of Pathology, Stanford University, Stanford, Calif; Sean N. Parker Center for Allergy and Asthma Research, Stanford University, Stanford, Calif
| | - Mats Ohlin
- Department of Immunotechnology, Lund University, Lund, Sweden
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2
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Ehlers AM, Hartog Jager CF, Knulst AC, Otten HG. Distinction between peanut allergy and tolerance by characterization of B cell receptor repertoires. Allergy 2021; 76:2753-2764. [PMID: 33969502 PMCID: PMC8453529 DOI: 10.1111/all.14897] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 04/08/2021] [Accepted: 04/25/2021] [Indexed: 12/11/2022]
Abstract
Background Specific IgE against a peanut 2S albumin (Ara h 2 or 6) is the best predictor of clinically relevant peanut sensitization. However, sIgE levels of peanut allergic and those of peanut sensitized but tolerant patients partly overlap, highlighting the need for improved diagnostics to prevent incorrect diagnosis and consequently unnecessary food restrictions. Thus, we sought to explore differences in V(D)J gene transcripts coding for peanut 2S albumin‐specific monoclonal antibodies (mAbs) from allergic and sensitized but tolerant donors. Methods 2S albumin‐binding B‐cells were single‐cell sorted from peripheral blood of peanut allergic (n=6) and tolerant (n=6) donors sensitized to Ara h2 and/or 6 (≥ 0.1 kU/l) and non‐atopic controls (n=5). h 2 and/or 6 (≥ 0.1 kU/l). Corresponding h heavy and light chain gene transcripts were heterologously expressed as mAbs and tested for specificity to native Ara h2 and 6. HCDR3 sequence motifs were identified by Levenshtein distances and hierarchically clustering. Results The frequency of 2S albumin‐binding B cells was increased in allergic (median: 0.01%) compared to tolerant (median: 0.006%) and non‐atopic donors (median: 0.0015%, p = 0.008). The majority of mAbs (74%, 29/39) bound specifically to Ara h 2 and/or 6. Non‐specific mAbs (9/10) were mainly derived from non‐atopic controls. In allergic donors, 89% of heavy chain gene transcripts consisted of VH3 family genes, compared with only 54% in sensitized but tolerant and 63% of non‐atopic donors. Additionally, certain HCDR3 sequence motifs were associated with allergy (n = 4) or tolerance (n = 3) upon hierarchical clustering of their Levenshtein distances. Conclusions Peanut allergy is associated with dominant VH3 family gene usage and certain public antibody sequences (HCDR3 motifs).
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Affiliation(s)
- Anna M. Ehlers
- Center for Translational Immunology University Medical Center Utrecht, Utrecht University Utrecht The Netherlands
- Department of Dermatology/Allergology University Medical Center Utrecht, Utrecht University Utrecht The Netherlands
| | - Constance F. Hartog Jager
- Center for Translational Immunology University Medical Center Utrecht, Utrecht University Utrecht The Netherlands
- Department of Dermatology/Allergology University Medical Center Utrecht, Utrecht University Utrecht The Netherlands
| | - André C. Knulst
- Center for Translational Immunology University Medical Center Utrecht, Utrecht University Utrecht The Netherlands
- Department of Dermatology/Allergology University Medical Center Utrecht, Utrecht University Utrecht The Netherlands
| | - Henny G. Otten
- Center for Translational Immunology University Medical Center Utrecht, Utrecht University Utrecht The Netherlands
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3
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Krause T, Röckendorf N, Meckelein B, Sinnecker H, Schwager C, Möckel S, Jappe U, Frey A. IgE Epitope Profiling for Allergy Diagnosis and Therapy - Parallel Analysis of a Multitude of Potential Linear Epitopes Using a High Throughput Screening Platform. Front Immunol 2020; 11:565243. [PMID: 33117349 PMCID: PMC7561404 DOI: 10.3389/fimmu.2020.565243] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2020] [Accepted: 09/08/2020] [Indexed: 12/22/2022] Open
Abstract
Immunoglobulin E (IgE) is pivotal for manifestation and persistence of most immediate-type allergies and some asthma phenotypes. Consequently, IgE represents a crucial target for both, diagnostic purposes as well as therapeutic approaches. In fact, allergen-specific immunotherapy – aiming to re-route an IgE-based inflammatory response into an innocuous immune reaction against the allergen – is the only curative approach for IgE-mediated allergic diseases known so far. However, this requires the cognate allergen to be known. Unfortunately, even in well-characterized allergics or asthmatics, often just a small fraction of total IgE can be assigned to specific target allergens. To overcome this knowledge gap, we have devised an analytical platform for unbiased IgE target epitope detection. The system relies on chemically produced random peptide libraries immobilized on polystyrene beads (“one-bead-one-compound (OBOC) libraries”) capable to present millions of different peptide motifs simultaneously to immunoglobulins from biological samples. Beads binding IgE are highlighted with a fluorophore-labeled anti-IgE antibody allowing fluorescence-based detection and isolation of positives, which then can be characterized by peptide sequencing. Setting-up this platform required an elaborate optimization process including proper choice of background suppressants, secondary antibody and fluorophore label as well as incubation conditions. For optimal performance our procedure involves a sophisticated pre-adsorption step to eliminate beads that react nonspecifically with anti-IgE secondary antibodies. This step turned out to be important for minimizing detection of “false positive” motifs that otherwise would erroneously be classified as IgE epitopes. In validation studies we were able to retrieve artificial test-peptide beads spiked into our library by using IgE directed against those test-peptides at physiological concentrations (≤20 IU/ml of specific IgE), and disease-relevant bead-bound epitopes of the major peanut allergen Ara h 2 by screening with sera from peanut allergics. Thus, we established a platform with which one can find and validate new immunoglobulin targets using patient material which displays a largely unknown immunoglobulin repertoire.
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Affiliation(s)
- Thorsten Krause
- Division of Mucosal Immunology and Diagnostics, Priority Area Asthma and Allergy, Research Center Borstel, Borstel, Germany.,Airway Research Center North, German Center for Lung Research (DZL), Borstel, Germany
| | - Niels Röckendorf
- Division of Mucosal Immunology and Diagnostics, Priority Area Asthma and Allergy, Research Center Borstel, Borstel, Germany.,Airway Research Center North, German Center for Lung Research (DZL), Borstel, Germany
| | - Barbara Meckelein
- Division of Mucosal Immunology and Diagnostics, Priority Area Asthma and Allergy, Research Center Borstel, Borstel, Germany.,Airway Research Center North, German Center for Lung Research (DZL), Borstel, Germany
| | - Heike Sinnecker
- Division of Mucosal Immunology and Diagnostics, Priority Area Asthma and Allergy, Research Center Borstel, Borstel, Germany.,Airway Research Center North, German Center for Lung Research (DZL), Borstel, Germany
| | - Christian Schwager
- Airway Research Center North, German Center for Lung Research (DZL), Borstel, Germany.,Division of Clinical Molecular Allergology, Priority Area Asthma and Allergy, Research Center Borstel, Borstel, Germany
| | - Stefanie Möckel
- Flow Cytometry Core Facility, Institute of Molecular Biology, Mainz, Germany
| | - Uta Jappe
- Airway Research Center North, German Center for Lung Research (DZL), Borstel, Germany.,Division of Clinical Molecular Allergology, Priority Area Asthma and Allergy, Research Center Borstel, Borstel, Germany.,Interdisciplinary Allergy Outpatient Clinic, Department of Pneumology, University of Lübeck, Lübeck, Germany
| | - Andreas Frey
- Division of Mucosal Immunology and Diagnostics, Priority Area Asthma and Allergy, Research Center Borstel, Borstel, Germany.,Airway Research Center North, German Center for Lung Research (DZL), Borstel, Germany
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4
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Flicker S, Zettl I, Tillib SV. Nanobodies-Useful Tools for Allergy Treatment? Front Immunol 2020; 11:576255. [PMID: 33117377 PMCID: PMC7561424 DOI: 10.3389/fimmu.2020.576255] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Accepted: 09/15/2020] [Indexed: 11/13/2022] Open
Abstract
In the last decade single domain antibodies (nanobodies, VHH) qualified through their unique characteristics have emerged as accepted and even advantageous alternative to conventional antibodies and have shown great potential as diagnostic and therapeutic tools. Currently nanobodies find their main medical application area in the fields of oncology and neurodegenerative diseases. According to late-breaking information, nanobodies specific for coronavirus spikes have been generated these days to test their suitability as useful therapeutics for future outbreaks. Their superior properties such as chemical stability, high affinity to a broad spectrum of epitopes, low immunogenicity, ease of their generation, selection and production proved nanobodies also to be remarkable to investigate their efficacy for passive treatment of type I allergy, an exaggerated immune reaction to foreign antigens with increasing global prevalence.
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Affiliation(s)
- Sabine Flicker
- Division of Immunopathology, Institute of Pathophysiology and Allergy Research, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria
| | - Ines Zettl
- Division of Immunopathology, Institute of Pathophysiology and Allergy Research, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria
| | - Sergei V. Tillib
- Institute of Gene Biology, Russian Academy of Sciences, Moscow, Russia
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5
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Glesner J, Kapingidza AB, Godzwon M, Offermann LR, Mueller GA, DeRose EF, Wright P, Richardson CM, Woodfolk JA, Vailes LD, Wünschmann S, London RE, Chapman MD, Ohlin M, Chruszcz M, Pomés A. A Human IgE Antibody Binding Site on Der p 2 for the Design of a Recombinant Allergen for Immunotherapy. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2019; 203:2545-2556. [PMID: 31554696 PMCID: PMC6810898 DOI: 10.4049/jimmunol.1900580] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Accepted: 08/15/2019] [Indexed: 01/31/2023]
Abstract
Der p 2 is one of the most important allergens from the house dust mite Dermatophagoides pteronyssinus Identification of human IgE Ab binding epitopes can be used for rational design of allergens with reduced IgE reactivity for therapy. Antigenic analysis of Der p 2 was performed by site-directed mutagenesis based on the x-ray crystal structure of the allergen in complex with a Fab from the murine IgG mAb 7A1 that binds an epitope overlapping with human IgE binding sites. Conformational changes upon Ab binding were confirmed by nuclear magnetic resonance using a 7A1-single-chain variable fragment. In addition, a human IgE Ab construct that interferes with mAb 7A1 binding was isolated from a combinatorial phage-display library constructed from a mite-allergic patient and expressed as two recombinant forms (single-chain Fab in Pichia pastoris and Fab in Escherichia coli). These two IgE Ab constructs and the mAb 7A1 failed to recognize two Der p 2 epitope double mutants designed to abolish the allergen-Ab interaction while preserving the fold necessary to bind Abs at other sites of the allergen surface. A 10-100-fold reduction in binding of IgE from allergic subjects to the mutants additionally showed that the residues mutated were involved in IgE Ab binding. In summary, mutagenesis of a Der p 2 epitope defined by x-ray crystallography revealed an IgE Ab binding site that will be considered for the design of hypoallergens for immunotherapy.
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Affiliation(s)
- Jill Glesner
- Indoor Biotechnologies, Inc., Charlottesville, VA 22903
| | | | | | | | - Geoffrey A Mueller
- National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC 27709; and
| | - Eugene F DeRose
- National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC 27709; and
| | - Paul Wright
- University of Virginia, Charlottesville, VA 22903
| | | | | | - Lisa D Vailes
- Indoor Biotechnologies, Inc., Charlottesville, VA 22903
| | | | - Robert E London
- National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC 27709; and
| | | | | | | | - Anna Pomés
- Indoor Biotechnologies, Inc., Charlottesville, VA 22903;
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6
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Hjort C, Schiøtz PO, Ohlin M, Würtzen PA, Christensen LH, Hoffmann HJ. The number and affinity of productive IgE pairs determine allergen activation of mast cells. J Allergy Clin Immunol 2017; 140:1167-1170.e2. [DOI: 10.1016/j.jaci.2017.04.014] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Revised: 03/18/2017] [Accepted: 04/10/2017] [Indexed: 11/30/2022]
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7
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Chen JB, James LK, Davies AM, Wu YCB, Rimmer J, Lund VJ, Chen JH, McDonnell JM, Chan YC, Hutchins GH, Chang TW, Sutton BJ, Kariyawasam HH, Gould HJ. Antibodies and superantibodies in patients with chronic rhinosinusitis with nasal polyps. J Allergy Clin Immunol 2016; 139:1195-1204.e11. [PMID: 27658758 PMCID: PMC5380656 DOI: 10.1016/j.jaci.2016.06.066] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2015] [Revised: 05/07/2016] [Accepted: 06/13/2016] [Indexed: 01/19/2023]
Abstract
Background Chronic rhinosinusitis with nasal polyps is associated with local immunoglobulin hyperproduction and the presence of IgE antibodies against Staphylococcus aureus enterotoxins (SAEs). Aspirin-exacerbated respiratory disease is a severe form of chronic rhinosinusitis with nasal polyps in which nearly all patients express anti-SAEs. Objectives We aimed to understand antibodies reactive to SAEs and determine whether they recognize SAEs through their complementarity-determining regions (CDRs) or framework regions. Methods Labeled staphylococcal enterotoxin (SE) A, SED, and SEE were used to isolate single SAE-specific B cells from the nasal polyps of 3 patients with aspirin-exacerbated respiratory disease by using fluorescence-activated cell sorting. Recombinant antibodies with “matched” heavy and light chains were cloned as IgG1, and those of high affinity for specific SAEs, assayed by means of ELISA and surface plasmon resonance, were recloned as IgE and antigen-binding fragments. IgE activities were tested in basophil degranulation assays. Results Thirty-seven SAE-specific, IgG- or IgA-expressing B cells were isolated and yielded 6 anti-SAE clones, 2 each for SEA, SED, and SEE. Competition binding assays revealed that the anti-SEE antibodies recognize nonoverlapping epitopes in SEE. Unexpectedly, each anti-SEE mediated SEE-induced basophil degranulation, and IgG1 or antigen-binding fragments of each anti-SEE enhanced degranulation by the other anti-SEE. Conclusions SEEs can activate basophils by simultaneously binding as antigens in the conventional manner to CDRs and as superantigens to framework regions of anti-SEE IgE in anti-SEE IgE-FcεRI complexes. Anti-SEE IgG1s can enhance the activity of anti-SEE IgEs as conventional antibodies through CDRs or simultaneously as conventional antibodies and as “superantibodies” through CDRs and framework regions to SEEs in SEE–anti-SEE IgE-FcεRI complexes.
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Affiliation(s)
- Jiun-Bo Chen
- Randall Division of Cell and Molecular Biophysics, King's College London, London, United Kingdom; Genomics Research Center, Academia Sinica, Taipei, Taiwan
| | - Louisa K James
- Randall Division of Cell and Molecular Biophysics, King's College London, London, United Kingdom; MRC & Asthma UK Centre for Allergic Mechanisms of Asthma, King's College London, Guy's Campus, London, United Kingdom
| | - Anna M Davies
- Randall Division of Cell and Molecular Biophysics, King's College London, London, United Kingdom; MRC & Asthma UK Centre for Allergic Mechanisms of Asthma, King's College London, Guy's Campus, London, United Kingdom
| | - Yu-Chang Bryan Wu
- Randall Division of Cell and Molecular Biophysics, King's College London, London, United Kingdom; MRC & Asthma UK Centre for Allergic Mechanisms of Asthma, King's College London, Guy's Campus, London, United Kingdom
| | - Joanne Rimmer
- Allergy and Rhinology, Royal National Throat Nose Ear Hospital, London, United Kingdom
| | - Valerie J Lund
- Allergy and Rhinology, Royal National Throat Nose Ear Hospital, London, United Kingdom
| | - Jou-Han Chen
- Genomics Research Center, Academia Sinica, Taipei, Taiwan
| | - James M McDonnell
- Randall Division of Cell and Molecular Biophysics, King's College London, London, United Kingdom; MRC & Asthma UK Centre for Allergic Mechanisms of Asthma, King's College London, Guy's Campus, London, United Kingdom
| | - Yih-Chih Chan
- Randall Division of Cell and Molecular Biophysics, King's College London, London, United Kingdom; MRC & Asthma UK Centre for Allergic Mechanisms of Asthma, King's College London, Guy's Campus, London, United Kingdom
| | - George H Hutchins
- Randall Division of Cell and Molecular Biophysics, King's College London, London, United Kingdom
| | - Tse Wen Chang
- Genomics Research Center, Academia Sinica, Taipei, Taiwan
| | - Brian J Sutton
- Randall Division of Cell and Molecular Biophysics, King's College London, London, United Kingdom; MRC & Asthma UK Centre for Allergic Mechanisms of Asthma, King's College London, Guy's Campus, London, United Kingdom
| | - Harsha H Kariyawasam
- Allergy and Rhinology, Royal National Throat Nose Ear Hospital, London, United Kingdom
| | - Hannah J Gould
- Randall Division of Cell and Molecular Biophysics, King's College London, London, United Kingdom; MRC & Asthma UK Centre for Allergic Mechanisms of Asthma, King's College London, Guy's Campus, London, United Kingdom.
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8
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Levin M, Rotthus S, Wendel S, Najafi N, Källström E, Focke-Tejkl M, Valenta R, Flicker S, Ohlin M. Multiple independent IgE epitopes on the highly allergenic grass pollen allergen Phl p 5. Clin Exp Allergy 2015; 44:1409-19. [PMID: 25262820 PMCID: PMC4278554 DOI: 10.1111/cea.12423] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2014] [Revised: 07/06/2014] [Accepted: 08/15/2014] [Indexed: 11/30/2022]
Abstract
Background Group 5 allergens are small proteins that consist of two domains. They belong to the most potent respiratory allergens. Objective To determine the binding sites and to study allergic patients' IgE recognition of the group 5 allergen (Phl p 5) from timothy grass pollen using human monoclonal IgE antibodies that have been isolated from grass pollen allergic patients. Methods Using recombinant isoallergens, fragments, mutants and synthetic peptides of Phl p 5, as well as peptide-specific antibodies, the interaction of recombinant human monoclonal IgE and Phl p 5 was studied using direct binding and blocking assays. Cross-reactivity of monoclonal IgE with group 5 allergens in several grasses was studied and inhibition experiments with patients' polyclonal IgE were performed. Results Monoclonal human IgE showed extensive cross-reactivity with group 5 allergens in several grasses. Despite its small size of 29 kDa, four independent epitope clusters on isoallergen Phl p 5.0101, two in each domain, were recognized by human IgE. Isoallergen Phl p 5.0201 carried two of these epitopes. Inhibition studies with allergic patients' polyclonal IgE suggest the presence of additional IgE epitopes on Phl p 5. Conclusions & Clinical Relevance Our results reveal the presence of a large number of independent IgE epitopes on the Phl p 5 allergen explaining the high allergenic activity of this protein and its ability to induce severe allergic symptoms. High-density IgE recognition may be a general feature of many potent allergens and form a basis for the development of improved diagnostic and therapeutic procedures in allergic disease.
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Affiliation(s)
- M Levin
- Department of Immunotechnology, Lund University, Lund, Sweden
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9
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Levin M, Otten H, von Wachenfeldt C, Ohlin M. A folded and immunogenic IgE-hyporeactive variant of the major allergen Phl p 1 produced in Escherichia coli. BMC Biotechnol 2015; 15:52. [PMID: 26054338 PMCID: PMC4460866 DOI: 10.1186/s12896-015-0150-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2014] [Accepted: 04/22/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Group 1 grass pollen allergens are a major cause of allergic disease. Specific immunotherapy involving controlled administration of allergens can be used as a disease-modifying treatment for such disease. Recombinant allergen variants with reduced IgE binding capacity may be used as component in such vaccines, as they may induce fewer treatment side effects than materials currently in use. A mutated variant of the immunodominant C-terminal domain of the group 1 grass pollen allergen Phl p 1 was recently established through an approach that used a set of human monoclonal IgE as a guide to identify mutations that disturbed IgE-allergen interactions. Further analysis of this domain is required to establish its potential for use in treatment. METHODS GST-tagged wild-type and mutated C-terminal domains of Phl p 1 were produced in Escherichia coli TUNER(DE3). The products were purified by affinity chromatography on immobilized glutathione. GST was removed by enzymatic cleavage and tag-free products were purified by size exclusion chromatography. Products were assessed by SDS-PAGE, circular dichroism spectroscopy, differential scanning fluorimetry and dynamic light scattering. Rats were immunized with GST-tagged and tag-free mutated C-terminal domain of Phl p 1. Antigen-binding properties of induced antibodies were assessed by immunochemical analysis. RESULTS The mutated domain has a structure very similar to that of the wild-type domain as determined by circular dichroism, but a reduced thermal stability. Immunization of rats demonstrates that this IgE-hyporeactive domain, despite its three sequence modifications (K8A, N11A, D55A), is able to induce antibodies that substantially block the binding of allergic subjects' IgE to the wild-type allergen. CONCLUSIONS It is concluded that this IgE-hyporeactive molecule can be produced in folded form and that it is able to induce an antibody response that efficiently competes with IgE recognition of Phl p 1. These findings suggest that it, or a further evolved variant thereof, is a candidate for use as a component in specific immunotherapy against grass pollen allergy.
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Affiliation(s)
- Mattias Levin
- Dept. of Immunotechnology, Lund University, Medicon Village building 406, S-223 81, Lund, Sweden.
| | - Harm Otten
- Crystallization facility at the MAX IV laboratory and Lund University, Lund, Sweden. .,Lund Protein Production Platform (LP3), Lund University, Lund, Sweden.
| | | | - Mats Ohlin
- Dept. of Immunotechnology, Lund University, Medicon Village building 406, S-223 81, Lund, Sweden.
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10
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Levin M, Davies AM, Liljekvist M, Carlsson F, Gould HJ, Sutton BJ, Ohlin M. Human IgE against the major allergen Bet v 1--defining an epitope with limited cross-reactivity between different PR-10 family proteins. Clin Exp Allergy 2014; 44:288-99. [PMID: 24447087 PMCID: PMC4215112 DOI: 10.1111/cea.12230] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2013] [Revised: 09/24/2013] [Accepted: 10/25/2013] [Indexed: 02/05/2023]
Abstract
Background The interaction between IgE and allergen is a key event at the initiation of an allergic response, and its characteristics have substantial effects on the clinical manifestation. Despite this, the molecular details of the interaction between human IgE and the major birch allergen Bet v 1, one of the most potent tree allergens, still remain poorly investigated. Objective To isolate Bet v 1-specific human monoclonal IgE and characterize their interaction with the allergen. Methods Recombinant human IgE were isolated from a combinatorial antibody fragment library and their interaction with Bet v 1 assessed using various immunological assays. The structure of one such IgE in the single-chain fragment variable format was determined using X-ray crystallography. Results We present four novel Bet v 1-specific IgE, for one of which we solve the structure, all with their genetic origin in the IGHV5 germline gene, and demonstrate that they target two non-overlapping epitopes on the surface of Bet v 1, thereby fulfilling the basic criteria for FcεRI cross-linkage. We further define these epitopes and for one epitope pinpoint single amino acid residues important for the interaction with human IgE. This provides a potential explanation, at the molecular level, for the differences in recognition of isoforms of Bet v 1 and other allergens in the PR-10 protein family displayed by IgE targeting this epitope. Finally, we present the first high-resolution structure of a human allergen-specific IgE fragment in the single-chain fragment variable (scFv) format. Conclusions and Clinical Relevance We here display the usefulness of allergen-specific human monoclonal IgE as a tool in studies of the crucial molecular interaction taking place at the initiation of an allergic response. Such studies may aid us in development of better diagnostic tools and guide us in the development of new therapeutic compounds.
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Affiliation(s)
- M Levin
- Department of Immunotechnology, Lund University, Lund, Sweden
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11
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Gadermaier E, Levin M, Flicker S, Ohlin M. The human IgE repertoire. Int Arch Allergy Immunol 2013; 163:77-91. [PMID: 24296690 DOI: 10.1159/000355947] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
IgE is a key mediator in allergic diseases. However, in strong contrast to other antibody isotypes, many details of the composition of the human IgE repertoire are poorly defined. The low levels of human IgE in the circulation and the rarity of IgE-producing B cells are important reasons for this lack of knowledge. In this review, we summarize the current knowledge on these repertoires both in terms of their complexity and activity, i.e. knowledge which despite the difficulties encountered when studying the molecular details of human IgE has been acquired in recent years. We also take a look at likely future developments, for instance through improvements in sequencing technology and methodology that allow the isolation of additional allergen-specific human antibodies mimicking IgE, as this certainly will support our understanding of human IgE in the context of human disease in the years to come.
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Affiliation(s)
- Elisabeth Gadermaier
- Division of Immunopathology, Department of Pathophysiology, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria
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12
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Levin M, Rydnert F, Källström E, Tan LW, Wormald PJ, Lindstedt M, Greiff L, Ohlin M. Phl p 1–Specific Human Monoclonal IgE and Design of a Hypoallergenic Group 1 Grass Pollen Allergen Fragment. THE JOURNAL OF IMMUNOLOGY 2013; 191:551-60. [DOI: 10.4049/jimmunol.1202051] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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Levin M, Ohlin M. Inconclusive evidence for or against positive antigen selection in the shaping of human immunoglobulin E repertoires: a call for new approaches. Int Arch Allergy Immunol 2013; 161:122-6. [PMID: 23343692 DOI: 10.1159/000345421] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2012] [Accepted: 10/24/2012] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND The mechanisms driving the development of immunoglobulin E (IgE) antibody repertoires are a matter of debate. Alternatives to the classical view on antibody development, involving somatic mutation and antigen-driven selection of high-affinity variants in germinal centers, have been proposed. METHODS We have re-analyzed the pattern of mutations in previously isolated and characterized human clonally unrelated IgE-encoding transcripts using the validated focused binomial methodology to find evidence in such genes of antigen-specific selection. RESULTS As expected there is a selection against replacement mutations in IgE framework regions. In contrast, in all examined cases but one (assessing IgE repertoires of parasite-infected individuals) there was no evidence in favor of either positive or negative selection in complementarity determining regions. Importantly, however, the validated method also failed to detect selection for replacement mutations in two, non-IgE, hypermutated antibody populations targeting tetanus toxoid and vaccinia virus, respectively. CONCLUSIONS Current methodology is unable to define with certainty, using commonly assessed IgE repertoire sizes, whether antigen selection is or is not a major driving force in the establishment of human IgE. New approaches are needed to address this matter.
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Affiliation(s)
- Mattias Levin
- Department of Immunotechnology, Lund University, Lund, Sweden
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Gadermaier E, Flicker S, Lupinek C, Steinberger P, Valenta R. Determination of allergen specificity by heavy chains in grass pollen allergen-specific IgE antibodies. J Allergy Clin Immunol 2012. [PMID: 23206656 DOI: 10.1016/j.jaci.2012.10.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
BACKGROUND Affinity and clonality of allergen-specific IgE antibodies are important determinants for the magnitude of IgE-mediated allergic inflammation. OBJECTIVE We sought to analyze the contribution of heavy and light chains of human allergen-specific IgE antibodies for allergen specificity and to test whether promiscuous pairing of heavy and light chains with different allergen specificity allows binding and might affect affinity. METHODS Ten IgE Fabs specific for 3 non-cross-reactive major timothy grass pollen allergens (Phl p 1, Phl p 2, and Phl p 5) obtained by means of combinatorial cloning from patients with grass pollen allergy were used to construct stable recombinant single chain variable fragments (ScFvs) representing the original Fabs and shuffled ScFvs in which heavy chains were recombined with light chains from IgE Fabs with specificity for other allergens by using the pCANTAB 5 E expression system. Possible ancestor genes for the heavy chain and light chain variable region-encoding genes were determined by using sequence comparison with the ImMunoGeneTics database, and their chromosomal locations were determined. Recombinant ScFvs were tested for allergen specificity and epitope recognition by means of direct and sandwich ELISA, and affinity by using surface plasmon resonance experiments. RESULTS The shuffling experiments demonstrate that promiscuous pairing of heavy and light chains is possible and maintains allergen specificity, which is mainly determined by the heavy chains. ScFvs consisting of different heavy and light chains exhibited different affinities and even epitope specificity for the corresponding allergen. CONCLUSION Our results indicate that allergen specificity of allergen-specific IgE is mainly determined by the heavy chains. Different heavy and light chain pairings in allergen-specific IgE antibodies affect affinity and epitope specificity and thus might influence clinical reactivity to allergens.
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Affiliation(s)
- Elisabeth Gadermaier
- Division of Immunopathology, Department of Pathophysiology and Allergy Research, Centre for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna General Hospital, Vienna, Austria
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Antibody repertoire complexity and effector cell biology determined by assays for IgE-mediated basophil and T-cell activation. J Immunol Methods 2012; 383:4-20. [PMID: 22683539 DOI: 10.1016/j.jim.2012.05.021] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2011] [Revised: 05/23/2012] [Accepted: 05/29/2012] [Indexed: 11/23/2022]
Abstract
Effector cell activation and T-cell activation, the latter mediated by facilitated antigen presentation, are immunological mechanisms that play crucial roles in the manifestation and maintenance of allergic disease. In addition to their relevance for the pathogenesis of allergy in-vivo, in-vitro assays based on these immunological mechanisms have been established and used for diagnostics, for monitoring the progression of disease and for the effect of specific immunotherapy as well as for basic research purposes. Here we review different parameters that affect effector cell activation and facilitated antigen uptake and presentation, including assay designs, readout parameters and critical experimental conditions. Central to the two immunological mechanisms is complex formation between allergen-specific IgE, allergen, and cell surface-anchored immunoglobulin receptor; the high affinity IgE-receptor FcεRI on basophils and mast cells, and the low affinity IgE-receptor FcεRII (CD23) on B-cells. Accordingly, the effect of IgE repertoire complexity and allergen diversity on effector cell and facilitated antigen presentation is discussed in detail.
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Abstract
Here, we discuss various questions related to IgE epitopes: What are the technical possibilities and pitfalls, what is currently known, how can we put this information into hypothetical frameworks and the unavoidable question: how useful is this information for patient care or allergenicity prediction? We discuss the information obtained by (i) 3D structures of allergen-antibody complexes; (ii) analysis of allergen analogues; (iii) mimics without obvious structural similarity; (iv) mAbs competing with IgE; (v) repertoire analysis of cloned IgEs, and other developments. Based on limited data, four suggestions are presented in the literature: (i) IgE might be more cross-reactive than IgG; (ii) IgE might be more often directed to immunologically 'uninviting' surfaces; (iii) IgE epitopes may tend to cluster and (iv) IgE paratopes might have a higher intrinsic flexibility. While these are not proven facts, they still can generate hypotheses for future research. The hypothesis is put forward that the IgE repertoire of switched B-cells is less influenced by positive selection, because positive selection might not be able to rescue IgE-switched B cells. While this might be of interest for the discussion about mechanisms leading to allergen-sensitization, we need to be modest in answering the 'clinical relevance' question. Current evidence indicates the IgE-epitope repertoire is too big to make specific IgE epitopes a realistic target for diagnosis, treatment or allergenicity prediction. In-depth analysis of a few selected IgE epitope-peptides or mimitopes derived from allergen-sequences and from random peptide libraries, respectively, might well prove rewarding in relation to diagnosis and prognosis of allergy, particularly food allergy.
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Affiliation(s)
- R C Aalberse
- Department of Immunopathology, Sanquin Research and Academic Medical Centre, Amsterdam, the Netherlands.
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17
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Hecker J, Diethers A, Etzold S, Seismann H, Michel Y, Plum M, Bredehorst R, Blank S, Braren I, Spillner E. Generation and epitope analysis of human monoclonal antibody isotypes with specificity for the Timothy grass major allergen Phl p 5a. Mol Immunol 2011; 48:1236-44. [PMID: 21474184 DOI: 10.1016/j.molimm.2011.03.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2011] [Accepted: 03/08/2011] [Indexed: 11/19/2022]
Abstract
The scarcity of monoclonal human IgE antibodies with specificity for defined allergens is a bottleneck for the molecular characterisation of allergens and their epitopes. Insights into the characteristics of such antibodies may allow for analyses of the molecular basis underlying allergenicity and cross-reactivity, standardisation of allergens as well as improvement of allergy diagnostics and therapeutics. Here we report the generation and application of the first set of authentic human IgG, IgE and IgA antibodies. On the basis of a Phl p 5a specific antibody fragment, a lambda light chain and the IgG1, IgG4, IgE, IgA1, and IgA2 heavy chains, the corresponding human immunoglobulins were constructed and produced in mammalian cells. In parallel, a murine hybridoma line with specificity for Phl p 5a was established, recloned and produced as human chimeric IgE. After purification, immunoreactivity of the antibodies with the allergen was assessed. Applicability in allergy diagnostics was confirmed by establishment of artificial human sera. Functionality of both antibodies was further demonstrated in receptor binding studies and mediator release assays using humanised rat basophil leukaemia cells (RBL-SX38) suggesting the presence of spatially separate epitopes. By using Phl p 5 fusion proteins and recombinant IgE in immunoblotting and mediator release assays we assigned the epitope of the authentic IgE to a looped stretch exclusively present in Phl p 5a. In summary, the Phl p 5-specific antibodies are the first full set of allergy-related antibody isotypes of their kind and represent valuable tools for studies of fundamental mechanisms and structure/function relationships in allergy.
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Affiliation(s)
- Julia Hecker
- Institute of Biochemistry and Molecular Biology, Department of Chemistry, University of Hamburg, Germany
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18
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Levin M, Tan LW, Baker L, Wormald PJ, Greiff L, Ohlin M. Diversity of immunoglobulin E-encoding transcripts in sinus mucosa of subjects diagnosed with non-allergic fungal eosinophilic sinusitis. Clin Exp Allergy 2011; 41:811-20. [PMID: 21561493 DOI: 10.1111/j.1365-2222.2011.03724.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND The role of allergy in the aetiopathogenesis of chronic rhinosinusitis (CRS) remains controversial. For example, in some cases with sinus fungal infections allergy can be demonstrated by standard tests. In other cases, such signs can be absent despite elevated levels of IgE-positive cells in sinus tissue and the presence of IgE and eosinophils in the sinus mucous. OBJECTIVE To define the nature of molecular diversity in antibodies of the IgE isotype at the site of local inflammation in subjects diagnosed with non-allergic fungal eosinophilic sinusitis (NAFES). METHODS The local occurrence and sequence characteristics of IgE-encoding transcripts in NAFES patients were investigated and compared with sequences found in subjects diagnosed with CRS featuring systemic allergy. These sequences have also been compared with other reported IgE-encoding transcriptomes. Results IGHV genes derived from major subgroups 1, 3, 4 and 5 and a diverse set of IGHD and IGHJ genes were shown to create the IgE repertoire in patients diagnosed with NAFES and CRS. The average lengths of the third hypervariable loop in these populations were 15.8 and 14.6 residues. The sequences showed evidence of extensive somatic hypermutation (mutation frequency: NAFES, 6.4 ± 3.2%; CRS, 7.0 ± 4.4%) with substitutions targeted to complementarity-determining regions. These sequence collections thus show extensive similarities to those found in other polyclonal Ig repertoires including those encoding IgE. CONCLUSION AND CLINICAL RELEVANCE We conclude that sinus IgE-encoding transcripts in subjects diagnosed with NAFES show evidence of conventional IgE responses and we suggest that allergens with characteristics of classical antigens should be investigated for a role in the local response occurring in NAFES. This investigation illustrates that assessment of local immunity might be an important diagnostic tool in conditions like NAFES with no systemic signs of allergy to identify or rule out an allergic component of the patient's disease.
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Affiliation(s)
- M Levin
- Department of Immunotechnology, Lund University, Lund, Sweden
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Akdis CA. New insights into mechanisms of immunoregulation in 2007. J Allergy Clin Immunol 2008; 122:700-709. [PMID: 19014761 DOI: 10.1016/j.jaci.2008.07.048] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2008] [Accepted: 07/11/2008] [Indexed: 11/25/2022]
Abstract
Substantial progress in understanding the mechanisms of immune regulation in allergic diseases and asthma has been made during the last year. In asthma, rhinitis, and atopic dermatitis the immune system is activated by allergens, autoantigens, and components of superimposed infectious agents. Immune regulation in the lymphatic organs and in the tissue has an important role in the control and suppression of allergic disease in all stages of the inflammatory process, such as cell migration to tissues, cells gaining an inflammatory and tissue-destructive phenotype in the tissues, and their interaction with resident tissue cells to augment the inflammation. After the discovery of regulatory T cells, the importance of their unique suppressive capacity was strongly emphasized for the suppression of effector T-cell responses. However, it seems that all 3 subsets of effector T(H)1, T(H)2, and T(H)17 cells, as well as regulatory T cells, regulate each other at the level of transcription, major cytokines, and surface molecules. This review highlights key advances in immune regulation that were published in the Journal of Allergy and Clinical Immunology.
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Affiliation(s)
- Cezmi A Akdis
- Swiss Institute of Allergy and Asthma Research (SIAF), Davos, Switzerland.
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Pedraza-Escalona M, Becerril-Luján B, Agundis C, Domínguez-Ramírez L, Pereyra A, Riaño-Umbarila L, Rodríguez-Romero A. Analysis of B-cell epitopes from the allergen Hev b 6.02 revealed by using blocking antibodies. Mol Immunol 2008; 46:668-76. [PMID: 18930549 DOI: 10.1016/j.molimm.2008.08.282] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2008] [Accepted: 08/27/2008] [Indexed: 11/19/2022]
Abstract
Hev b 6.02 (hevein), identified as a major allergen from natural rubber latex (NRL), is involved in the latex-fruit syndrome and also acts as a pathogenesis defense-related protein. Its 3D structure has been solved at high resolution, and its linear epitopes have already been reported. However, information about conformational epitopes is still controversial, even though it is relevant for an accurate diagnosis and treatment, as well as for the study of allergen-antibody molecular interactions. We sought to analyze the B-cell epitopes of Hev b 6.02 at a molecular and structural level, using specific recombinant antibodies. We obtained a murine monoclonal antibody (mAb 6E7) and three human single chain fragments (scFvs A6, H8, and G7) anti-Hev b 6.02 that were able to compete for hevein binding with serum IgEs from latex allergic patients. In vitro assays showed that the mAb 6E7 and scFv H8 recognized the area of Hev b 6.02 where the aromatic residues are exposed; while the scFv G7 defined the amino and carboxy-terminal regions that lie close to each other, as a different epitope. The structural modeling of the Hev b 6.02-scFv H8 and Hev b 6.02-scFv G7 complexes revealed the putative regions of two conformational epitopes. In one of these, the aromatic residues, as well as polar side chains are important for the interaction, suggesting that they are part of a dominant conformational epitope also presented on the Hev b 6.02-IgE interactions. Antibodies recognizing this important allergen have potential to be used to diagnose and ultimately treat latex allergy.
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Affiliation(s)
- Martha Pedraza-Escalona
- Instituto de Química, Universidad Nacional Autónoma de México, Circuito Exterior, Cd. Universitaria, Coyoacán, México, D.F. 04510, Mexico
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Persson J, Augustsson P, Laurell T, Ohlin M. Acoustic microfluidic chip technology to facilitate automation of phage display selection. FEBS J 2008; 275:5657-66. [DOI: 10.1111/j.1742-4658.2008.06691.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Lundberg K, Lindstedt M, Larsson K, Dexlin L, Wingren C, Ohlin M, Greiff L, Borrebaeck CA. Augmented Phl p 5-specific Th2 response after exposure of dendritic cells to allergen in complex with specific IgE compared to IgG1 and IgG4. Clin Immunol 2008; 128:358-65. [DOI: 10.1016/j.clim.2008.04.011] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2007] [Revised: 04/24/2008] [Accepted: 04/28/2008] [Indexed: 11/24/2022]
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Advances in basic and clinical immunology in 2007. J Allergy Clin Immunol 2008; 122:36-41. [DOI: 10.1016/j.jaci.2008.04.035] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2008] [Accepted: 04/25/2008] [Indexed: 12/20/2022]
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A common idiotype in IgE and its relation to recognition of the grass pollen allergen Phl p 2. Mol Immunol 2008; 45:2715-20. [DOI: 10.1016/j.molimm.2008.01.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2007] [Accepted: 01/07/2008] [Indexed: 11/23/2022]
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