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Mir Drikvand R, Sohrabi SM, Sohrabi SS, Samiei K. Molecular Identification and Characterization of Hevein Antimicrobial Peptide Genes in Two-Row and Six-Row Cultivars of Barley (Hordeum vulgare L.). Biochem Genet 2024:10.1007/s10528-024-10695-8. [PMID: 38386212 DOI: 10.1007/s10528-024-10695-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Accepted: 01/09/2024] [Indexed: 02/23/2024]
Abstract
Heveins are one of the most important groups of plant antimicrobial peptides. So far, various roles in plant growth and development and in response to biotic and abiotic stresses have reported for heveins. The present study aimed to identify and characterize the hevein genes in two-row and six-row cultivars of barley. In total, thirteen hevein genes were identified in the genome of two-row and six-row cultivars of barley. The identified heveins were identical in two-row and six-row cultivars of barley and showed a high similarity with heveins from other plant species. The hevein coding sequences produced open reading frames (ORFs) ranged from 342 to 1002 bp. Most of the identified hevein genes were intronless, and the others had only one intron. The hevein ORFs produced proteins ranged from 113 to 333 amino acids. Search for conserved functional domains showed CBD and LYZ domains in barley heveins. All barley heveins comprised extracellular signal peptides ranged from 19 to 35 amino acids. The phylogenetic analysis divided barley heveins into two groups. The promoter analysis showed regulatory elements with different frequencies between two-row and six-row cultivars. These cis-acting elements included elements related to growth and development, hormone response, and environmental stresses. The expression analysis showed high expression level of heveins in root and reproductive organs of both two-row and six-row cultivars. The expression analysis also showed that barley heveins is induced by both biotic and abiotic stresses. The results of antimicrobial activity prediction showed the highest antimicrobial activity in CBD domain of barley heveins. The findings of the current study can improve our knowledge about the role of hevein genes in plant and can be used for future studies.
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Affiliation(s)
- Reza Mir Drikvand
- Department of Plant Genetics and Breeding, Islamic Azad University, Khorramabad Branch, Khorramabad, Iran.
| | - Seyyed Mohsen Sohrabi
- Department of Production Engineering and Plant Genetics, Faculty of Agriculture, Shahid Chamran University, Ahvaz, Iran
| | - Seyed Sajad Sohrabi
- Department of Production Engineering and Plant Genetics, Faculty of Agriculture, Lorestan University, Khorramabad, Iran
| | - Kamran Samiei
- Department of Plant Genetics and Breeding, Islamic Azad University, Khorramabad Branch, Khorramabad, Iran
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Plum M, Tjerrild L, Raiber T, Bantleon F, Bantleon S, Miehe M, Jabs F, Seismann H, Möbs C, Pfützner W, Jakob T, Andersen GR, Spillner E. Structural and functional analyses of antibodies specific for modified core N-glycans suggest a role in T H 2 responses. Allergy 2023; 78:121-130. [PMID: 35726192 PMCID: PMC10083920 DOI: 10.1111/all.15417] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2021] [Revised: 04/19/2022] [Accepted: 05/20/2022] [Indexed: 12/29/2022]
Abstract
BACKGROUND Immune responses to N-glycan structures from allergens and parasites are often associated with pronounced, high affinity IgE reactivities. Cross-reactive carbohydrate determinants (CCDs) are constituted by modified N-glycan core structures and represent the most frequently recognized epitopes in allergic immune responses. Although recently accepted as potentially allergenic epitopes, the biological and clinical relevance as well as structural and functional characteristics of CCD-specific antibodies remain elusive. METHODS In order to gain structural insights into the recognition of CCDs, two specific antibody fragments were isolated from a leporid immune repertoire library and converted into human/leporid IgE and IgG formats. The antibody formats were assessed by ELISA and surface plasmon resonance, structural and functional analyses were performed by X-ray crystallography, mediator release, and ELIFAB assays. RESULTS The recombinant IgE exhibited highly specific interactions with different types of CCDs on numerous CCD-carrying glycoproteins. Crystal structures of two CCD-specific antibodies, one of which in complex with a CCD-derived disaccharide emphasize that mechanisms of core glycan epitope recognition are as specific as those governing protein epitope recognition. The rIgE triggered immediate cellular responses via FcεRI cross-linking and mediated facilitated antigen presentation by binding of IgE/antigen complexes to CD23, a process that also could be blocked by IgG of allergic patients. CONCLUSIONS Our study provides evidence for the relevance of N-glycan recognition in TH 2 responses and corroborates that IgE and IgG antibodies to ubiquitous carbohydrate epitopes can be equivalent to those directed against proteinaceous epitopes with implications for diagnostic and immunotherapeutic concepts.
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Affiliation(s)
- Melanie Plum
- Immunological Biotechnology, Department of Biological and Chemical Engineering, Aarhus University, Aarhus, Denmark.,Division of Clinical and Molecular Allergology, Research Center Borstel, Leibniz Lung Center, German Center for Lung Research (DZL), Borstel, Germany
| | - Luna Tjerrild
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
| | - Tim Raiber
- Immunological Biotechnology, Department of Biological and Chemical Engineering, Aarhus University, Aarhus, Denmark.,Institute of Biochemistry and Molecular Biology, Department of Chemistry, University of Hamburg, Hamburg, Germany
| | - Frank Bantleon
- Immunological Biotechnology, Department of Biological and Chemical Engineering, Aarhus University, Aarhus, Denmark
| | - Sara Bantleon
- Immunological Biotechnology, Department of Biological and Chemical Engineering, Aarhus University, Aarhus, Denmark.,Institute of Biochemistry and Molecular Biology, Department of Chemistry, University of Hamburg, Hamburg, Germany
| | - Michaela Miehe
- Immunological Biotechnology, Department of Biological and Chemical Engineering, Aarhus University, Aarhus, Denmark
| | - Frederic Jabs
- Immunological Biotechnology, Department of Biological and Chemical Engineering, Aarhus University, Aarhus, Denmark.,Institute of Biochemistry and Molecular Biology, Department of Chemistry, University of Hamburg, Hamburg, Germany
| | - Henning Seismann
- Department of Oncology and Hematology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Christian Möbs
- Clinical & Experimental Allergology, Department of Dermatology and Allergology, Philipps University Marburg, Marburg, Germany
| | - Wolfgang Pfützner
- Clinical & Experimental Allergology, Department of Dermatology and Allergology, Philipps University Marburg, Marburg, Germany
| | - Thilo Jakob
- Department of Dermatology and Allergy, University Medical Center Giessen, Justus Liebig University, Giessen, Germany
| | - Gregers R Andersen
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
| | - Edzard Spillner
- Immunological Biotechnology, Department of Biological and Chemical Engineering, Aarhus University, Aarhus, Denmark
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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: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [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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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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Jensen‐Jarolim E, Bax HJ, Bianchini R, Capron M, Corrigan C, Castells M, Dombrowicz D, Daniels‐Wells TR, Fazekas J, Fiebiger E, Gatault S, Gould HJ, Janda J, Josephs DH, Karagiannis P, Levi‐Schaffer F, Meshcheryakova A, Mechtcheriakova D, Mekori Y, Mungenast F, Nigro EA, Penichet ML, Redegeld F, Saul L, Singer J, Spicer JF, Siccardi AG, Spillner E, Turner MC, Untersmayr E, Vangelista L, Karagiannis SN. AllergoOncology - the impact of allergy in oncology: EAACI position paper. Allergy 2017; 72:866-887. [PMID: 28032353 PMCID: PMC5498751 DOI: 10.1111/all.13119] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/23/2016] [Indexed: 12/19/2022]
Abstract
Th2 immunity and allergic immune surveillance play critical roles in host responses to pathogens, parasites and allergens. Numerous studies have reported significant links between Th2 responses and cancer, including insights into the functions of IgE antibodies and associated effector cells in both antitumour immune surveillance and therapy. The interdisciplinary field of AllergoOncology was given Task Force status by the European Academy of Allergy and Clinical Immunology in 2014. Affiliated expert groups focus on the interface between allergic responses and cancer, applied to immune surveillance, immunomodulation and the functions of IgE-mediated immune responses against cancer, to derive novel insights into more effective treatments. Coincident with rapid expansion in clinical application of cancer immunotherapies, here we review the current state-of-the-art and future translational opportunities, as well as challenges in this relatively new field. Recent developments include improved understanding of Th2 antibodies, intratumoral innate allergy effector cells and mediators, IgE-mediated tumour antigen cross-presentation by dendritic cells, as well as immunotherapeutic strategies such as vaccines and recombinant antibodies, and finally, the management of allergy in daily clinical oncology. Shedding light on the crosstalk between allergic response and cancer is paving the way for new avenues of treatment.
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Affiliation(s)
- E. Jensen‐Jarolim
- The Interuniversity Messerli Research InstituteUniversity of Veterinary Medicine ViennaMedical University of ViennaViennaAustria
- Institute of Pathophysiology & Allergy ResearchCenter of Pathophysiology, Infectiology & ImmunologyMedical University ViennaViennaAustria
| | - H. J. Bax
- Division of Genetics & Molecular MedicineFaculty of Life Sciences and MedicineSt. John's Institute of DermatologyKing's College LondonLondonUK
- Division of Cancer StudiesFaculty of Life Sciences & MedicineKing's College LondonGuy's HospitalLondonUK
| | - R. Bianchini
- The Interuniversity Messerli Research InstituteUniversity of Veterinary Medicine ViennaMedical University of ViennaViennaAustria
| | - M. Capron
- LIRIC‐Unité Mixte de Recherche 995 INSERMUniversité de Lille 2CHRU de LilleLilleFrance
| | - C. Corrigan
- Division of Asthma, Allergy and Lung BiologyMedical Research Council and Asthma UK Centre in Allergic Mechanisms in AsthmaKing's College LondonLondonUK
| | - M. Castells
- Division of Rheumatology, Immunology and AllergyDepartment of MedicineBrigham and Women's HospitalHarvard Medical SchoolBostonMAUSA
| | - D. Dombrowicz
- INSERMCHU LilleEuropean Genomic Institute of DiabetesInstitut Pasteur de LilleU1011 – récepteurs nucléaires, maladies cardiovasculaires et diabèteUniversité de LilleLilleFrance
| | - T. R. Daniels‐Wells
- Division of Surgical OncologyDepartment of SurgeryDavid Geffen School of Medicine at UCLALos AngelesCAUSA
| | - J. Fazekas
- The Interuniversity Messerli Research InstituteUniversity of Veterinary Medicine ViennaMedical University of ViennaViennaAustria
- Institute of Pathophysiology & Allergy ResearchCenter of Pathophysiology, Infectiology & ImmunologyMedical University ViennaViennaAustria
| | - E. Fiebiger
- Division of Gastroenterology, Hepatology and Nutrition ResearchDepartment of Medicine ResearchChildren's University Hospital BostonBostonMAUSA
| | - S. Gatault
- LIRIC‐Unité Mixte de Recherche 995 INSERMUniversité de Lille 2CHRU de LilleLilleFrance
| | - H. J. Gould
- Division of Asthma, Allergy and Lung BiologyMedical Research Council and Asthma UK Centre in Allergic Mechanisms in AsthmaKing's College LondonLondonUK
- Randall Division of Cell and Molecular BiophysicsKing's College LondonLondonUK
- NIHR Biomedical Research Centre at Guy's and St. Thomas’ Hospitals and King's College LondonKing's College LondonGuy's HospitalLondonUK
| | - J. Janda
- Center PigmodInstitute of Animal Physiology and GeneticsAcademy of Sciences of Czech RepublicLibechovCzech Republic
| | - D. H. Josephs
- Division of Genetics & Molecular MedicineFaculty of Life Sciences and MedicineSt. John's Institute of DermatologyKing's College LondonLondonUK
- Division of Cancer StudiesFaculty of Life Sciences & MedicineKing's College LondonGuy's HospitalLondonUK
| | - P. Karagiannis
- Division of Genetics & Molecular MedicineFaculty of Life Sciences and MedicineSt. John's Institute of DermatologyKing's College LondonLondonUK
- NIHR Biomedical Research Centre at Guy's and St. Thomas’ Hospitals and King's College LondonKing's College LondonGuy's HospitalLondonUK
| | - F. Levi‐Schaffer
- Pharmacology and Experimental Therapeutics UnitFaculty of MedicineSchool of PharmacyThe Institute for Drug ResearchThe Hebrew University of JerusalemJerusalemIsrael
| | - A. Meshcheryakova
- Institute of Pathophysiology & Allergy ResearchCenter of Pathophysiology, Infectiology & ImmunologyMedical University ViennaViennaAustria
| | - D. Mechtcheriakova
- Institute of Pathophysiology & Allergy ResearchCenter of Pathophysiology, Infectiology & ImmunologyMedical University ViennaViennaAustria
| | - Y. Mekori
- Sackler Faculty of MedicineTel‐Aviv UniversityTel‐AvivIsrael
| | - F. Mungenast
- Institute of Pathophysiology & Allergy ResearchCenter of Pathophysiology, Infectiology & ImmunologyMedical University ViennaViennaAustria
| | - E. A. Nigro
- IRCCS San Raffaele Scientific InstituteMilanItaly
| | - M. L. Penichet
- Division of Surgical OncologyDepartment of SurgeryDavid Geffen School of Medicine at UCLALos AngelesCAUSA
- Department of Microbiology, Immunology, and Molecular GeneticsDavid Geffen School of Medicine at UCLALos AngelesCAUSA
- Jonsson Comprehensive Cancer CenterUniversity of CaliforniaLos AngelesCAUSA
| | - F. Redegeld
- Division of PharmacologyFaculty of ScienceUtrecht Institute for Pharmaceutical SciencesUtrecht UniversityUtrechtThe Netherlands
| | - L. Saul
- Division of Genetics & Molecular MedicineFaculty of Life Sciences and MedicineSt. John's Institute of DermatologyKing's College LondonLondonUK
- Division of Cancer StudiesFaculty of Life Sciences & MedicineKing's College LondonGuy's HospitalLondonUK
| | - J. Singer
- Institute of Pathophysiology & Allergy ResearchCenter of Pathophysiology, Infectiology & ImmunologyMedical University ViennaViennaAustria
| | - J. F. Spicer
- Division of Cancer StudiesFaculty of Life Sciences & MedicineKing's College LondonGuy's HospitalLondonUK
- NIHR Biomedical Research Centre at Guy's and St. Thomas’ Hospitals and King's College LondonKing's College LondonGuy's HospitalLondonUK
| | | | - E. Spillner
- Immunological EngineeringDepartment of EngineeringAarhus UniversityAarhusDenmark
| | - M. C. Turner
- ISGlobalCentre for Research in Environmental Epidemiology (CREAL)BarcelonaSpain
- Universitat Pompeu Fabra (UPF)BarcelonaSpain
- CIBER Epidemiología y Salud Pública (CIBERESP)MadridSpain
- McLaughlin Centre for Population Health Risk AssessmentUniversity of OttawaOttawaONCanada
| | - E. Untersmayr
- Institute of Pathophysiology & Allergy ResearchCenter of Pathophysiology, Infectiology & ImmunologyMedical University ViennaViennaAustria
| | - L. Vangelista
- Department of Biomedical SciencesNazarbayev University School of MedicineAstanaKazakhstan
| | - S. N. Karagiannis
- Division of Genetics & Molecular MedicineFaculty of Life Sciences and MedicineSt. John's Institute of DermatologyKing's College LondonLondonUK
- NIHR Biomedical Research Centre at Guy's and St. Thomas’ Hospitals and King's College LondonKing's College LondonGuy's HospitalLondonUK
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Bantleon F, Wolf S, Seismann H, Dam S, Lorentzen A, Miehe M, Jabs F, Jakob T, Plum M, Spillner E. Human IgE is efficiently produced in glycosylated and biologically active form in lepidopteran cells. Mol Immunol 2016; 72:49-56. [DOI: 10.1016/j.molimm.2016.02.013] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Revised: 02/13/2016] [Accepted: 02/22/2016] [Indexed: 02/02/2023]
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Haka J, Niemi MH, Iljin K, Reddy VS, Takkinen K, Laukkanen ML. Isolation of Mal d 1 and Api g 1 - specific recombinant antibodies from mouse IgG Fab fragment libraries - Mal d 1-specific antibody exhibits cross-reactivity against Bet v 1. BMC Biotechnol 2015; 15:34. [PMID: 26013405 PMCID: PMC4446070 DOI: 10.1186/s12896-015-0157-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Accepted: 05/01/2015] [Indexed: 11/12/2022] Open
Abstract
Background Around 3–5% of the population suffer from IgE-mediated food allergies in Western countries and the number of food-allergenic people is increasing. Individuals with certain pollen allergies may also suffer from a sensitisation to proteins in the food products. As an example a person sensitised to the major birch pollen allergen, Bet v 1, is often sensitised to its homologues, such as the major allergens of apple, Mal d 1, and celery, Api g 1, as well. Development of tools for the reliable, sensitive and quick detection of allergens present in various food products is essential for allergic persons to prevent the consumption of substances causing mild and even life-threatening immune responses. The use of monoclonal antibodies would ensure the specific detection of the harmful food content for a sensitised person. Methods Mouse IgG antibody libraries were constructed from immunised mice and specific recombinant antibodies for Mal d 1 and Api g 1 were isolated from the libraries by phage display. More detailed characterisation of the resulting antibodies was carried out using ELISA, SPR experiments and immunoprecipitation assays. Results The allergen-specific Fab fragments exhibited high affinity towards the target recombinant allergens. Furthermore, the Fab fragments also recognised native allergens from natural sources. Interestingly, isolated Mal d 1-specific antibody bound also to Bet v 1, the main allergen eliciting the cross-reactivity syndrome between the birch pollen and apple. Despite the similarities in Api g 1 and Bet v 1 tertiary structures, the isolated Api g 1-specific antibodies showed no cross-reactivity to Bet v 1. Conclusions Here, high-affinity allergen-specific recombinant antibodies were isolated with interesting binding properties. With further development, these antibodies can be utilised as tools for the specific and reliable detection of allergens from different consumable products. This study gives new preliminary insights to elucidate the mechanism behind the pollen-food syndrome and to study the IgG epitope of the allergens.
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Affiliation(s)
- Jaana Haka
- VTT Technical Research Centre of Finland Ltd, P.O. Box 1000, Espoo, FI-02044 VTT, Finland.
| | - Merja H Niemi
- Department of Chemistry, University of Eastern Finland, Joensuu Campus, P.O. Box 111, Joensuu, FI-80101, Finland.
| | - Kristiina Iljin
- VTT Technical Research Centre of Finland Ltd, P.O. Box 1000, Espoo, FI-02044 VTT, Finland.
| | - Vanga Siva Reddy
- International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi, 110067, India.
| | - Kristiina Takkinen
- VTT Technical Research Centre of Finland Ltd, P.O. Box 1000, Espoo, FI-02044 VTT, Finland.
| | - Marja-Leena Laukkanen
- VTT Technical Research Centre of Finland Ltd, P.O. Box 1000, Espoo, FI-02044 VTT, Finland.
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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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9
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Hairul Bahara NH, Tye GJ, Choong YS, Ong EBB, Ismail A, Lim TS. Phage display antibodies for diagnostic applications. Biologicals 2013; 41:209-16. [DOI: 10.1016/j.biologicals.2013.04.001] [Citation(s) in RCA: 218] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2013] [Revised: 03/29/2013] [Accepted: 04/02/2013] [Indexed: 11/23/2022] Open
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Sosa-rodriguez T, Declerck S, Granet F, Gaurel S, Van Damme EJM, Dupré de Boulois H. Hevea brasiliensis and Urtica dioica impact the in vitro mycorrhization of neighbouring Medicago truncatula seedlings. Symbiosis 2013; 60:123-32. [DOI: 10.1007/s13199-013-0248-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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11
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Hecker J, Diethers A, Schulz D, Sabri A, Plum M, Michel Y, Mempel M, Ollert M, Jakob T, Blank S, Braren I, Spillner E. An IgE epitope of Bet v 1 and fagales PR10 proteins as defined by a human monoclonal IgE. Allergy 2012; 67:1530-7. [PMID: 23066955 DOI: 10.1111/all.12045] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/31/2012] [Indexed: 01/03/2023]
Abstract
BACKGROUND Analyses of the molecular basis underlying allergenicity and allergen cross-reactivity, as well as improvement of allergy diagnostics and therapeutics, are hampered by the lack of human monoclonal IgE antibodies and knowledge about their epitopes. Here, we addressed the consecutive generation and epitope delineation of a human monoclonal IgE against the prototypic allergen Bet v 1. METHODS Phage-display scFv hybrid libraries of allergic donor-derived VH epsilon and synthetic VL were established from 107 mononuclear cells. An obtained scFv was converted into human immunoglobulin formats including IgE. Using variants of Bet v 1, the epitope of the antibody was mapped and extrapolated to other PR10 proteins. RESULTS The obtained antibodies exhibited pronounced reactivity with Bet v 1, but were not reactive with the homologous PR10 protein Mal d 1. The epitope as defined by the IgE paratope and a set of chimeric Bet v 1 fusion proteins and fragments could be assigned to a C-terminal helix-structured motif comprised by amino acid residues 132-154, including the critical residue E149. Grafting this motif re-established the reactivity of the per se nonreactive Mal d 1 framework. Cross-reactivities predicted by primary structure analyses of different isoforms and PR10 proteins were verified by allergen chip-based analyses. CONCLUSIONS The obtained results demonstrate that hybrid IgE repertoires represent a source for human antibodies with genuine paratopes. The IgE-derived information about the IgE epitope nature of Bet v 1 and homologues allows for detailed insights into molecular aspects of allergenicity and cross-reactivity within the PR10 protein family.
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Affiliation(s)
- J. Hecker
- Department of Chemistry, Institute of Biochemistry and Molecular Biology; University of Hamburg; Hamburg; Germany
| | - A. Diethers
- Department of Chemistry, Institute of Biochemistry and Molecular Biology; University of Hamburg; Hamburg; Germany
| | - D. Schulz
- Department of Chemistry, Institute of Biochemistry and Molecular Biology; University of Hamburg; Hamburg; Germany
| | - A. Sabri
- Department of Chemistry, Institute of Biochemistry and Molecular Biology; University of Hamburg; Hamburg; Germany
| | - M. Plum
- Department of Chemistry, Institute of Biochemistry and Molecular Biology; University of Hamburg; Hamburg; Germany
| | - Y. Michel
- Department of Chemistry, Institute of Biochemistry and Molecular Biology; University of Hamburg; Hamburg; Germany
| | - M. Mempel
- Department of Dermatology, Venerology, and Allergology; Georg-August-University; Göttingen; Germany
| | - M. Ollert
- Department of Dermatology and Allergy, Clinical Research Division of Molecular and Clinical Allergotoxicology; Technische Universität München; Munich; Germany
| | - T. Jakob
- Department of Dermatology; University Medical Center Freiburg; Freiburg; Germany
| | - S. Blank
- Department of Chemistry, Institute of Biochemistry and Molecular Biology; University of Hamburg; Hamburg; Germany
| | - I. Braren
- Hamburg Center for Experimental Therapy Research; University Medical Center Hamburg; Hamburg; Germany
| | - E. Spillner
- Department of Chemistry, Institute of Biochemistry and Molecular Biology; University of Hamburg; Hamburg; Germany
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12
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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13
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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14
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Christensen LH, Riise E, Bang L, Zhang C, Lund K. Isoallergen Variations Contribute to the Overall Complexity of Effector Cell Degranulation: Effect Mediated through Differentiated IgE Affinity. J I 2010; 184:4966-72. [DOI: 10.4049/jimmunol.0904038] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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15
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Jylhä S, Mäkinen-Kiljunen S, Haahtela T, Söderlund H, Takkinen K, Laukkanen ML. Selection of recombinant IgE antibodies binding the beta-lactoglobulin allergen in a conformation-dependent manner. J Immunol Methods 2009; 350:63-70. [PMID: 19647743 DOI: 10.1016/j.jim.2009.07.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2009] [Revised: 06/26/2009] [Accepted: 07/21/2009] [Indexed: 12/21/2022]
Abstract
Cow's milk allergy (CMA) is a common food allergy, especially among infants and young children. Approximately 85% of milk-allergic children outgrow their allergy by the age of three but the remaining 15% remain allergic. Bovine beta-lactoglobulin (BLG) is one of the major allergens in cow's milk. There is a definite need for the specific and sensitive detection of allergenic substances. Validated methods are obligatory to demonstrate allergen contamination and even fatal hidden allergens and, thus, to prevent life-threatening conditions of allergic persons. In this study, we constructed human IgE scFv libraries from an adult milk-allergic patient and isolated the first recombinant IgE antibodies specific to a food allergen, BLG. The selection of the IgE antibody libraries with two distinct panning procedures resulted in the enrichment of four clones having different BLG-binding profiles; two of the clones recognize the native BLG whereas the other two recognize only the heat-denatured form of BLG. For further characterization, the scFv fragments were converted to Fab fragments with human IgG1 isotype. The D1 Fab fragment, binding native BLG with nanomolar affinity, also partially inhibited serum IgE binding to BLG. These BLG-specific IgE antibodies can be applied for the detection of both native and denatured BLG in cow's milk products and furthermore, for the optimization of manufacturing processes to develop safe hypoallergenic milk products.
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Affiliation(s)
- Sirpa Jylhä
- VTT Technical Research Centre of Finland, P.O. Box 1000, FIN-02044 VTT, Finland
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16
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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17
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Persson H, Flicker S, Sadegh MK, Greiff L, Valenta R, Ohlin M. 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] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2007] [Accepted: 01/07/2008] [Indexed: 11/23/2022]
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18
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Niemi M, Jylhä S, Laukkanen ML, Söderlund H, Mäkinen-Kiljunen S, Kallio JM, Hakulinen N, Haahtela T, Takkinen K, Rouvinen J. Molecular Interactions between a Recombinant IgE Antibody and the β-Lactoglobulin Allergen. Structure 2007; 15:1413-21. [DOI: 10.1016/j.str.2007.09.012] [Citation(s) in RCA: 99] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2007] [Revised: 09/03/2007] [Accepted: 09/09/2007] [Indexed: 10/22/2022]
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19
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Persson H, Sadegh MK, Greiff L, Ohlin M. Delineating the specificity of an IgE-encoding transcriptome. J Allergy Clin Immunol 2007; 120:1186-92. [PMID: 17825890 DOI: 10.1016/j.jaci.2007.06.041] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2007] [Revised: 06/21/2007] [Accepted: 06/25/2007] [Indexed: 11/27/2022]
Abstract
BACKGROUND Although much is known about the reactivity of polyclonal populations of antibodies targeting the wide array of allergens produced by timothy (Phleum pratense) and other grass species, little is known about the finer details at the level of individual antibody specificities. OBJECTIVE We sought to investigate the IgE repertoire as it occurs in a patient with grass pollen allergy. METHODS For this purpose, a human IgE library was used, constructed from peripheral blood B cells of an individual with timothy allergy. The library was screened by using phage display against a panel of 6 timothy allergens (Phl p 1, Phl p 2, Phl p 4, Phl p 5, Phl p 6, and Phl p 11). RESULTS Highly diverse antibody fragments with respect to gene usage were identified. The binders were specific for their respective target antigen, except for clones selected on Phl p 6 that also recognized Phl p 5, most likely reflecting the high sequence homology between these allergens. Interestingly, by using this approach, we were able to determine the specificity of more than 25% of all IgE-producing transcripts in this individual with allergy. CONCLUSION The human IgE repertoire is produced by a limited number of highly related B-cell clones and as such is restricted in its recognition of a limited number of antigens. CLINICAL IMPLICATIONS Human allergen-specific antibodies can, by defining the specificity of IgE responses, aid in the development of allergy vaccines or even by themselves be used in passive immunotherapy.
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Affiliation(s)
- Helena Persson
- Department of Immunotechnology, Lund University, Lund, Sweden
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20
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Braren I, Blank S, Seismann H, Deckers S, Ollert M, Grunwald T, Spillner E. Generation of Human Monoclonal Allergen-Specific IgE and IgG Antibodies from Synthetic Antibody Libraries. Clin Chem 2007; 53:837-44. [PMID: 17395713 DOI: 10.1373/clinchem.2006.078360] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Abstract
Background: Allergen-specific IgE and IgG antibodies play pivotal roles in the induction and progression of allergic hypersensitivity reactions. Consequently, monoclonal human IgE and IgG4 antibodies with defined specificity for allergens should be useful in allergy research and diagnostic tests. We used combinatorial antibody libraries and subsequent recombinant production to make and assess IgE, IgG1, and IgG4 allergen-specific antibodies.
Methods: We used phage display to select a synthetic single-chain antibody fragment (scFv) library against 3 different allergens, from bee venom, bovine milk, and apple. The scFv obtained were converted into IgG1, IgG4, and IgE antibody formats and assessed for their biochemical properties by ELISA, immunoblotting, and fluorescence-activated cell sorting.
Results: Two different antibody formats for each IgG1, IgG4, and IgE antibody were produced in mammalian cells as disulfide-linked and glycosylated Ig, which were usable in allergen-specific ELISA assays and immunoblots. In addition, the recombinant IgE antibodies mediated the binding of allergens to HEK-293 cells transfected with the high-affinity IgE receptor, and this binding was blocked by corresponding IgG antibodies.
Conclusions: The use of synthetic libraries for the generation of allergen-specific recombinant IgE and IgG antibodies should have broad applications in allergological research and diagnosis.
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Affiliation(s)
- Ingke Braren
- Institute of Biochemistry and Food Sciences, Division of Biochemistry and Molecular Biology, University of Hamburg, Hamburg, Germany
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21
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Abstract
This paper reviews immunoaffinity CE procedures developed since 1998 for drug, hormone, and disease marker analyses of body fluids and tissues. Immunoaffinity CE and related techniques are described. Examples of clinical applications are included.
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Affiliation(s)
- Lotta K Amundsen
- Technical Research Centre of Finland (VTT), P.O. Box 1000, FIN-02044 VTT, Finland
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22
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Andréasson U, Flicker S, Lindstedt M, Valenta R, Greiff L, Korsgren M, Borrebaeck CAK, Ohlin M. The human IgE-encoding transcriptome to assess antibody repertoires and repertoire evolution. J Mol Biol 2006; 362:212-27. [PMID: 16905150 DOI: 10.1016/j.jmb.2006.06.062] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2006] [Revised: 06/01/2006] [Accepted: 06/05/2006] [Indexed: 11/30/2022]
Abstract
Upon encounter with antigen, the B lymphocyte population responds by producing a diverse set of antigen-specific antibodies of various isotypes. The vast size of the responding populations makes it very difficult to study clonal evolution and repertoire composition occurring during these processes in humans. Here, we have explored an approach utilizing the H-EPSILON-encoding transcriptome to investigate aspects of repertoire diversity during the season of antigen exposure. We show through sequencing of randomly picked transcripts that the sizes of patients' repertoires are relatively small. This specific aspect of the transcriptome allows us to construct evolutionary trees pinpointing features of somatic hypermutation as it occurs in humans. Despite the small size of the repertoires, they are highly diverse with respect to VDJ gene usage, suggesting that the H-EPSILON-encoding transcriptome is a faithful mimic of other class-switched isotypes. Importantly, it is possible to use antibody library and selection technologies to define the specificity of clonotypes identified by random sequencing. The small size of the H-EPSILON-encoding transcriptome of peripheral blood B cells, the simple identification of clonally related sets of genes in this population, and the power of library and selection technologies ensure that this approach will allow us to investigate antibody evolution in human B lymphocytes of known specificity. As H-EPSILON repertoires show many of the hallmarks of repertoires encoding other isotypes, we suggest that studies of this type will have an impact on our understanding of human antibody evolution even beyond that occurring in the IgE-producing B cell population.
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