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Zhou Y, Zhu K, Li Q, Zhou D, Ren Y, Liao Y, Cao P, Gong Y, Cui Y. Immunobiological properties and structure analysis of group 13 allergen from Blomia tropicalis and its IgE-mediated cross-reactivity. Int J Biol Macromol 2024; 254:127788. [PMID: 37926306 DOI: 10.1016/j.ijbiomac.2023.127788] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Revised: 10/16/2023] [Accepted: 10/28/2023] [Indexed: 11/07/2023]
Abstract
Blomia tropicalis is an important species of allergenic mite. Structurally related cross-reactive allergens are involved in pathogenesis of clinical symptoms. The present study focused on recombinant allergen rBlo t 13 from B. tropicalis, including investigation of its structure, immunological properties, IgE-mediated cross-reactivity. In this work, the prokaryotic expression plasmids pET-28(a)-Blo t 13, pET-28(a)-Der f 13, and pET-28(a)-Tyr p 13 were constructed, transformed into E. coli Rosetta (DE3) pLysS, and purified by nickel affinity chromatography, respectively. By using ELISA, the IgE-binding rates were detected for rBlo t 13 and its epitope peptides, as well as the cross-reactivity among rBlo t 13, rDer f 13, and rTyr p 13. The tertiary structure of rBlo t 13 was resolved using X-ray diffraction at 2.0 Å resolution. Using IgE-ELISA, the IgE binding rate of rBlo t 13 was 60 % with Blomia tropicalis-positive sera. In the experiments of ELISA for cross-reactivity with rBlo t 13 on solid phase, the inhibition rates were 65 %, 57 % and 63 % for rBlo t 13, rDer f 13, and rTyr p 13, respectively. The structure of Blo t 13 protein contains a β-barrel structure which is composed of 10 β strands and has 2 α helices at the end of the barrel. Comparison of the tertiary structures of rBlo t 13, rDer f 13, and rTyr p 13 revealed that the β-barrel structure is highly conserved, consistent with the alignment of amino acid sequences. We obtained the recombinant protein rBlo t 13, demonstrated its cross-reactivity with Der f 13 and Tyr p 13 due to their structural similarity.
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Affiliation(s)
- Ying Zhou
- Department of Pediatrics Laboratory, The Affiliated Wuxi Children's Hospital of Jiangnan University, Wuxi 214023, PR China
| | - Keli Zhu
- Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, PR China
| | - Qingqing Li
- Clinical Research Center, The Affiliated Wuxi People's Hospital of Nanjing Medical University, Wuxi 214023, PR China
| | - Dongmei Zhou
- Clinical Research Center, The Affiliated Wuxi People's Hospital of Nanjing Medical University, Wuxi 214023, PR China
| | - Yaning Ren
- Clinical Research Center, The Affiliated Wuxi People's Hospital of Nanjing Medical University, Wuxi 214023, PR China
| | - Yuanfen Liao
- Clinical Research Center, The Affiliated Wuxi People's Hospital of Nanjing Medical University, Wuxi 214023, PR China
| | - Peng Cao
- Faculty of Environment and Life, Beijing University of Technology, Beijing, China
| | - Yong Gong
- Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, PR China.
| | - Yubao Cui
- Clinical Research Center, The Affiliated Wuxi People's Hospital of Nanjing Medical University, Wuxi 214023, PR China.
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Baru A, Devi C, Mukhopadhyay T, Dogra N. Anti bacterial function of secreted human FABP3. Biochim Biophys Acta Gen Subj 2023; 1867:130472. [PMID: 37788726 DOI: 10.1016/j.bbagen.2023.130472] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Revised: 09/12/2023] [Accepted: 09/28/2023] [Indexed: 10/05/2023]
Abstract
FABP3 belongs to a large family of cytoplasmic fatty acid binding proteins that are expressed in a tissue-specific manner. It is predominantly expressed in breast, muscle and heart. During our exploratory studies on the role of FABP3 in tumorigenesis and our consequent attempts to study the molecular mechanism responsible for the oncogenic potential of FABP3, we came across an unexpected role of FABP3 as an anti-bacterial protein. Presence of the protein was detected in culture media of cell lines stably over-expressing human FABP3. Conditioned medium from these FABP3 over-expressing cells exerted a distinct anti-bacterial activity against E. coli. Our results indicate that binding of FABP3 to the bacterial cell surface contributes to its anti-bacterial activity. Incubation of E. coli bacterial cells with FABP3 protein led to disruption of the physical integrity of bacterial cell membrane causing leakage of cellular components. Further, in silico analysis predicted strong binding of FABP3 to the antibiotic binding sites on the bacterial ribosome. Interestingly, we found that FABP3 is a naturally occurring secretory protein present in milk in abundance as confirmed by western blot and ELISA. Thus, our experimental data together with in silico analysis suggests that FABP3 is secreted in milk, has an anti-bacterial function, shows activity against E. coli by disrupting bacterial membrane and targeting the ribosome, and may play a protective role against bacterial infection in newborns.
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Affiliation(s)
- Ambica Baru
- National Centre for Human Genome Studies and Research, Panjab University, Sector-14, Chandigarh-160014, India
| | - Chandra Devi
- National Centre for Human Genome Studies and Research, Panjab University, Sector-14, Chandigarh-160014, India
| | - Tapas Mukhopadhyay
- National Centre for Human Genome Studies and Research, Panjab University, Sector-14, Chandigarh-160014, India.
| | - Nilambra Dogra
- National Centre for Human Genome Studies and Research, Panjab University, Sector-14, Chandigarh-160014, India.
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Stevenson GA, Kirshner D, Bennion BJ, Yang Y, Zhang X, Zemla A, Torres MW, Epstein A, Jones D, Kim H, Bennett WFD, Wong SE, Allen JE, Lightstone FC. Clustering Protein Binding Pockets and Identifying Potential Drug Interactions: A Novel Ligand-Based Featurization Method. J Chem Inf Model 2023; 63:6655-6666. [PMID: 37847557 PMCID: PMC10647021 DOI: 10.1021/acs.jcim.3c00722] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Indexed: 10/18/2023]
Abstract
Protein-ligand interactions are essential to drug discovery and drug development efforts. Desirable on-target or multitarget interactions are the first step in finding an effective therapeutic, while undesirable off-target interactions are the first step in assessing safety. In this work, we introduce a novel ligand-based featurization and mapping of human protein pockets to identify closely related protein targets and to project novel drugs into a hybrid protein-ligand feature space to identify their likely protein interactions. Using structure-based template matches from PDB, protein pockets are featured by the ligands that bind to their best co-complex template matches. The simplicity and interpretability of this approach provide a granular characterization of the human proteome at the protein-pocket level instead of the traditional protein-level characterization by family, function, or pathway. We demonstrate the power of this featurization method by clustering a subset of the human proteome and evaluating the predicted cluster associations of over 7000 compounds.
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Affiliation(s)
- Garrett A. Stevenson
- Computational
Engineering Division, Lawrence Livermore
National Laboratory, Livermore, California 94550, United States
| | - Dan Kirshner
- Biosciences
and Biotechnology Division, Lawrence Livermore
National Laboratory, Livermore, California 94550, United States
| | - Brian J. Bennion
- Biosciences
and Biotechnology Division, Lawrence Livermore
National Laboratory, Livermore, California 94550, United States
| | - Yue Yang
- Biosciences
and Biotechnology Division, Lawrence Livermore
National Laboratory, Livermore, California 94550, United States
| | - Xiaohua Zhang
- Biosciences
and Biotechnology Division, Lawrence Livermore
National Laboratory, Livermore, California 94550, United States
| | - Adam Zemla
- Global
Security Computing Applications Division, Lawrence Livermore National Laboratory, Livermore, California 94550, United States
| | - Marisa W. Torres
- Global
Security Computing Applications Division, Lawrence Livermore National Laboratory, Livermore, California 94550, United States
| | - Aidan Epstein
- Global
Security Computing Applications Division, Lawrence Livermore National Laboratory, Livermore, California 94550, United States
| | - Derek Jones
- Global
Security Computing Applications Division, Lawrence Livermore National Laboratory, Livermore, California 94550, United States
- Department
of Computer Science and Engineering, University
of California, San Diego, La Jolla, California 92093, United States
| | - Hyojin Kim
- Center
for Applied Scientific Computing, Lawrence
Livermore National Laboratory, Livermore, California 94550, United States
| | - W. F. Drew Bennett
- Biosciences
and Biotechnology Division, Lawrence Livermore
National Laboratory, Livermore, California 94550, United States
| | - Sergio E. Wong
- Biosciences
and Biotechnology Division, Lawrence Livermore
National Laboratory, Livermore, California 94550, United States
| | - Jonathan E. Allen
- Global
Security Computing Applications Division, Lawrence Livermore National Laboratory, Livermore, California 94550, United States
| | - Felice C. Lightstone
- Biosciences
and Biotechnology Division, Lawrence Livermore
National Laboratory, Livermore, California 94550, United States
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Pauli G, Wurmser C, Roos A, Kokou C, Huang HJ, D’souza N, Lupinek C, Zakzuk J, Regino R, Acevedo N, Caraballo L, Vrtala S, Valenta R. Frequent IgE recognition of Blomia tropicalis allergen molecules in asthmatic children and young adults in equatorial Africa. Front Immunol 2023; 14:1133935. [PMID: 37359512 PMCID: PMC10286740 DOI: 10.3389/fimmu.2023.1133935] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Accepted: 05/12/2023] [Indexed: 06/28/2023] Open
Abstract
Background Asthma is not well investigated in equatorial Africa and little is known about the disease-associated allergen molecules recognized by IgE from patients in this area. The aim was to study the molecular IgE sensitization profile of asthmatic children and young adults in a semi-rural area (Lambaréné) of an equatorial African country (Gabon), to identify the most important allergen molecules associated with allergic asthma in equatorial Africa. Methods Fifty-nine asthmatic patients, mainly children and few young adults, were studied by skin prick testing to Dermatophagoides pteronyssinus (Der p), D. farinae (Der f), cat, dog, cockroach, grass, Alternaria and peanut. Sera were obtained from a subset of 35 patients, 32 with positive and 3 with negative skin reaction to Der p and tested for IgE reactivity to 176 allergen molecules from different allergen sources by ImmunoCAP ISAC microarray technology and to seven recombinant Blomia tropicalis (Blo t) allergens by IgE dot blot assay. Results Thirty-three of the 59 patients (56%) were sensitized to Der p and 23 of them (39%) were also sensitized to other allergen sources, whereas 9 patients (15%) were only sensitized to allergen sources other than Der p. IgE serology analyses (n=35) showed high IgE-binding frequencies to the Blo t allergens Blo t 5 (43%), Blo t 21 (43%) and Blo t 2 (40%), whereas the Der p allergens rDer p 2, rDer p 21 and rDer p 5 (34%, 29% and 26%) were less frequently recognized. Only few patients showed IgE reactivity to allergens from other allergen sources, except to allergens containing carbohydrate determinants (CCDs) or to wasp venom allergens (i.e., antigen 5). Conclusion Our results thus demonstrate that IgE sensitization to mite allergens is very prevalent in asthmatics in Equatorial Africa with B. tropicalis allergen molecules representing the most important ones associated with allergic asthma.
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Affiliation(s)
- Gabrielle Pauli
- Faculty of Medicine, University Louis Pasteur, Strasbourg, France
- Hôpital Albert Schweitzer, Lambaréné, Gabon
| | - Carole Wurmser
- Faculty of Medicine, University Louis Pasteur, Strasbourg, France
- Hôpital Albert Schweitzer, Lambaréné, Gabon
| | - Antoine Roos
- Faculty of Medicine, University Louis Pasteur, Strasbourg, France
- Hôpital Albert Schweitzer, Lambaréné, Gabon
| | | | - Huey-Jy Huang
- Division of Immunopathology, Department of Pathophysiology and Allergy Research, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria
| | - Nishelle D’souza
- Division of Immunopathology, Department of Pathophysiology and Allergy Research, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria
| | - Christian Lupinek
- Division of Immunopathology, Department of Pathophysiology and Allergy Research, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria
| | - Josefina Zakzuk
- Institute for Immunological Research, Universidad de Cartagena, Cartagena, Colombia
| | - Ronald Regino
- Institute for Immunological Research, Universidad de Cartagena, Cartagena, Colombia
| | - Nathalie Acevedo
- Institute for Immunological Research, Universidad de Cartagena, Cartagena, Colombia
| | - Luis Caraballo
- Institute for Immunological Research, Universidad de Cartagena, Cartagena, Colombia
| | - Susanne Vrtala
- Division of Immunopathology, Department of Pathophysiology and Allergy Research, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria
| | - Rudolf Valenta
- Division of Immunopathology, Department of Pathophysiology and Allergy Research, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria
- National Research Center, Institute of Immunology FMBA of Russia, Moscow, Russia
- Laboratory for Immunopathology, Department of Clinical Immunology and Allergy, Sechenov First Moscow State Medical University, Moscow, Russia
- Karl Landsteiner University of Health Sciences, Krems, Austria
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Figo DD, Cordeiro Macedo PR, Gadermaier G, Remuzgo C, Castro FFM, Kalil J, Galvão CES, Santos KS. IgE and IgG4 Epitopes of Dermatophagoides and Blomia Allergens before and after Sublingual Immunotherapy. Int J Mol Sci 2023; 24:ijms24044173. [PMID: 36835585 PMCID: PMC9958541 DOI: 10.3390/ijms24044173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 02/04/2023] [Accepted: 02/13/2023] [Indexed: 02/22/2023] Open
Abstract
Sublingual immunotherapy (SLIT) is used worldwide to treat house dust mites (HDM) allergy. Epitope specific immunotherapy with peptide vaccines is used far less, but it is of great interest in the treatment of allergic reactions, as it precludes the drawbacks of allergen extracts. The ideal peptide candidates would bind to IgG, blocking IgE-binding. To better elucidate IgE and IgG4 epitope profiles during SLIT, sequences of main allergens, Der p 1, 2, 5, 7, 10, 23 and Blo t 5, 6, 12, 13, were included in a 15-mer peptide microarray and tested against pooled sera from 10 patients pre- and post-1-year SLIT. All allergens were recognized to some extent by at least one antibody isotype and peptide diversity was higher post-1-year SLIT for both antibodies. IgE recognition diversity varied among allergens and timepoints without a clear tendency. Der p 10, a minor allergen in temperate regions, was the molecule with more IgE-peptides and might be a major allergen in populations highly exposed to helminths and cockroaches, such as Brazil. SLIT-induced IgG4 epitopes were directed against several, but not all, IgE-binding regions. We selected a set of peptides that recognized only IgG4 or were able to induce increased ratios of IgG4:IgE after one year of treatment and might be potential targets for vaccines.
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Affiliation(s)
- Daniele Danella Figo
- LIM-19, Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo 05403-900, Brazil
- Laboratorio de Imunologia, INCOR, Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo 05403-900, Brazil
- Departamento de Clinica Medica, Disciplina de Imunologia Clinica e Alergia, Faculdade de Medicina da Universidade de Sao Paulo, Sao Paulo 01246-903, Brazil
| | - Priscilla Rios Cordeiro Macedo
- Departamento de Clinica Medica, Disciplina de Imunologia Clinica e Alergia, Faculdade de Medicina da Universidade de Sao Paulo, Sao Paulo 01246-903, Brazil
- Servico de Imunologia Clinica e Alergia, Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo 05403-000, Brazil
| | - Gabriele Gadermaier
- Department of Biosciences and Medical Biology, Paris Lodron University Salzburg, 5020 Salzburg, Austria
| | - Cesar Remuzgo
- Laboratorio de Imunologia, INCOR, Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo 05403-900, Brazil
| | - Fábio Fernandes Morato Castro
- Departamento de Clinica Medica, Disciplina de Imunologia Clinica e Alergia, Faculdade de Medicina da Universidade de Sao Paulo, Sao Paulo 01246-903, Brazil
- Servico de Imunologia Clinica e Alergia, Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo 05403-000, Brazil
- Instituto Nacional de Ciencia e Tecnologia de Investigação em Imunologia (iii-INCT), Sao Paulo 05403-900, Brazil
| | - Jorge Kalil
- LIM-19, Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo 05403-900, Brazil
- Laboratorio de Imunologia, INCOR, Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo 05403-900, Brazil
- Departamento de Clinica Medica, Disciplina de Imunologia Clinica e Alergia, Faculdade de Medicina da Universidade de Sao Paulo, Sao Paulo 01246-903, Brazil
- Instituto Nacional de Ciencia e Tecnologia de Investigação em Imunologia (iii-INCT), Sao Paulo 05403-900, Brazil
| | - Clovis Eduardo Santos Galvão
- Departamento de Clinica Medica, Disciplina de Imunologia Clinica e Alergia, Faculdade de Medicina da Universidade de Sao Paulo, Sao Paulo 01246-903, Brazil
- Servico de Imunologia Clinica e Alergia, Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo 05403-000, Brazil
| | - Keity Souza Santos
- LIM-19, Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo 05403-900, Brazil
- Laboratorio de Imunologia, INCOR, Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo 05403-900, Brazil
- Departamento de Clinica Medica, Disciplina de Imunologia Clinica e Alergia, Faculdade de Medicina da Universidade de Sao Paulo, Sao Paulo 01246-903, Brazil
- Instituto Nacional de Ciencia e Tecnologia de Investigação em Imunologia (iii-INCT), Sao Paulo 05403-900, Brazil
- Correspondence:
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Sánchez J, Sánchez Biol A, Múnera Biol M, García E, López JF. Immunoglobulin E and G autoantibodies against eosinophil proteins in children and adults with asthma and healthy subjects. World Allergy Organ J 2023; 16:100742. [PMID: 36941898 PMCID: PMC10024149 DOI: 10.1016/j.waojou.2023.100742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Revised: 12/15/2022] [Accepted: 12/21/2022] [Indexed: 02/04/2023] Open
Abstract
Background Autoimmune IgG response has been described in the pathogenesis of asthma in adults, but IgE autoimmunity has been little explored. Considering high levels of blood eosinophils and immunoglobulin E in asthmatic patients, the possibility of IgE autoantibody response to eosinophil proteins arises. Objective To explore the presence of IgE and IgG autoantibodies against Eosinophil peroxidase (EPX) and Eosinophil cationic protein (ECP). Methods Three steps were followed: 1) The frequency of IgE and IgG autoantibodies against EPX and ECP was investigated among asthmatic and healthy subjects. 2) The ability of IgE autoantibodies to induce an inflammatory response (basophil activation) was performed. 3) The capacity of autoantibodies to identify patients with severe asthma was evaluated. Results Asthmatic and healthy subjects had IgE and IgG autoantibodies against EPX and ECP. Anti-EPX IgE was significantly higher in asthmatic patients. Severe asthmatic patients had a higher frequency and higher levels of IgE and IgG autoantibodies compared to healthy subjects. There was not a correlation between autoantibodies and blood eosinophils. Children younger than 14 years of age had IgE and IgG autoantibodies against to EPX and ECP. IgE autoantibodies to EPX and ECP induced basophil activation in asthmatic patients. Conclusion In this study, we identify for the first time IgE autoantibodies against EPX and ECP in adults and children patients with asthma; IgE and IgG autoantibodies against EPX and ECP could serve as a predictive biomarker of the clinical severity.
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Affiliation(s)
- Jorge Sánchez
- Group of Clinical and Experimental Allergy, Clinic “IPS Universitaria”, University of Antioquia. Medellín, Colombia
- Corresponding author. Department of Allergology and Pediatrics, Faculty of Medicine, University of Antioquia. Medellín, Colombia.
| | - Andres Sánchez Biol
- Group of Clinical and Experimental Allergy, Clinic “IPS Universitaria”, University of Antioquia. Medellín, Colombia
- Faculty of Medicine, Corporation University “Rafael Nuñez”, Cartagena, Colombia
| | - Marlon Múnera Biol
- Faculty of Medicine, Corporation University “Rafael Nuñez”, Cartagena, Colombia
| | - Elizabeth García
- Universidad de Los Andes, Fundación Santa Fe de Bogota, Unidad Medica quirúrgica ORL. Bogota, Colombia
| | - Juan-Felipe López
- Group of Clinical and Experimental Allergy, Clinic “IPS Universitaria”, University of Antioquia. Medellín, Colombia
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Múnera M, Martínez D, Wortmann J, Zakzuk J, Keller W, Caraballo L, Puerta L. Structural and allergenic properties of the fatty acid binding protein from shrimp Litopenaeus vannamei. Allergy 2022; 77:1534-1544. [PMID: 34695231 DOI: 10.1111/all.15154] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Revised: 04/12/2021] [Accepted: 10/04/2021] [Indexed: 11/30/2022]
Abstract
BACKGROUND The shrimp Litopenaeus vannamei is an important source of food allergens but its allergenic repertoire is poorly characterized. Cross-reactivity between crustacean and mites has been reported, with tropomyosin, the most relevant allergen involved. The aim of this study was to investigate the structural and immunological properties of a recombinant Fatty Acid Binding Protein (FABP) family from L. vannamei (LvFABP). METHODS ELISA, skin prick test (SPT) and basophil activation assays were performed to determine IgE reactivity and allergenic activity of LvFABP. LC-MS/MS and Circular Dichroism experiments were done for structural analysis. B-cell epitope mapping with overlapping peptides, and cross-inhibition studies using human sera were done to identify antigenic regions and cross-reactivity. RESULTS The recombinant LvFABP bound serum IgE from 27% of 36 shrimp allergic patients and showed allergenic activity when tested for basophil activation and SPT in a selected number of them. CD-spectroscopy of LvFABP revealed that the protein is folded with a secondary structure composed of mainly β-strands and a smaller fraction of α helices. This is consistent with molecular modelling results, which exhibit a typical β barrel fold with two α-helices and ten β-strands. Epitope mapping identified two IgE-binding antigenic regions and inhibition assays found high cross-reactivity between LvFABP and Blo t 13, mediated by the antigenic region involving amino acids 54 to 72. CONCLUSIONS Our results show that LvFABP is a shrimp allergen that cross reacts with the house dust mite allergen Blo t 13 and has allergenic activity, which suggest that it could be clinically relevant in case of shellfish allergy. This new allergen, named Lit v 13, will also help to understand basic mechanisms of sensitization to shrimp.
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Affiliation(s)
- Marlon Múnera
- Institute for Immunological Research University of Cartagena Cartagena Colombia
| | - Dalgys Martínez
- Institute for Immunological Research University of Cartagena Cartagena Colombia
| | - Judith Wortmann
- Institute of Molecular Biosciences, BioTechMed Graz University of Graz Graz Austria
| | - Josefina Zakzuk
- Institute for Immunological Research University of Cartagena Cartagena Colombia
| | - Walter Keller
- Institute of Molecular Biosciences, BioTechMed Graz University of Graz Graz Austria
| | - Luis Caraballo
- Institute for Immunological Research University of Cartagena Cartagena Colombia
| | - Leonardo Puerta
- Institute for Immunological Research University of Cartagena Cartagena Colombia
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8
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Li WY, Cai ZL, Zhang BP, Chen JJ, Ji K. Identification of an immunodominant IgE epitope of Der p 39, a novel allergen of Dermatophagoides pteronyssinus. World Allergy Organ J 2022; 15:100651. [PMID: 35600837 PMCID: PMC9096144 DOI: 10.1016/j.waojou.2022.100651] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Revised: 03/11/2022] [Accepted: 04/12/2022] [Indexed: 11/16/2022] Open
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9
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Purification and characterisation of the dimeric group 12 allergen from Blomia tropicalis heterologously expressed by Escherichia coli Top10F´. Mol Biol Rep 2021; 48:3405-3416. [PMID: 33914278 DOI: 10.1007/s11033-021-06361-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Accepted: 04/16/2021] [Indexed: 10/21/2022]
Abstract
Successful research in the wide-ranging field of allergy is usually achieved by definition not only of physicochemical and immunological properties of natural, but also recombinant allergens. Blomia tropicalis mite is a well-known source for various groups of hypersensitivity-causing proteins. The goal of the present work was to produce, purify and characterise by in silico, biochemical and immunological methods the recombinant group-12 allergen of B. tropicalis. The recombinant Blo t 12 aggregation capacity as well as the affinity to antibodies from BALB/c immunised mice and B. tropicalis-sensitised human donors were investigated through in silico analyses, dynamic light scattering, SDS-PAGE, ELISA and Western blot. The presence of Blo t 12 within B. tropicalis extracts was also determined by ELISA and Western blot. High concentrations of dimeric rBlo t 12 were detected through SDS-PAGE next to other aggregates and the results were confirmed by data from DLS and Western blot. The YITVM peptide was predicted to be the most aggregation-prone region. The IgE-reactivity of rBlo t 12 was not completely abolished by aggregate formation but it was significantly decreased compared to rBlo t 5, or B. tropicalis extracts. Natural Blo t 12 may naturally dimerises, but it was detected in non-delipidified B. tropicalis extracts in low amounts. Given that this allergen may be a specific marker for B. tropicalis allergy, the recombinant Blo t 12 herein obtained is characterised as a mid-tier allergen in Brazilian atopic patients and may be useful for the improvement in precision allergy molecular diagnostic applications.
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