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Castaño N, Chua K, Kaushik A, Kim S, Cordts SC, Nafarzadegan CD, Hofmann GH, Seastedt H, Schuetz JP, Dunham D, Parsons ES, Tsai M, Cao S, Desai M, Sindher SB, Chinthrajah RS, Galli SJ, Nadeau KC, Tang SK. Combining avidin with CD63 improves basophil activation test accuracy in classifying peanut allergy. Allergy 2024; 79:445-455. [PMID: 37916710 PMCID: PMC10842984 DOI: 10.1111/all.15930] [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] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 10/11/2023] [Accepted: 10/12/2023] [Indexed: 11/03/2023]
Abstract
BACKGROUND Conventional basophil activation tests (BATs) measure basophil activation by the increased expression of CD63. Previously, fluorophore-labeled avidin, a positively-charged molecule, was found to bind to activated basophils, which tend to expose negatively charged granule constituents during degranulation. This study further compares avidin versus CD63 as basophil activation biomarkers in classifying peanut allergy. METHODS Seventy subjects with either a peanut allergy (N = 47), a food allergy other than peanut (N = 6), or no food allergy (N = 17) were evaluated. We conducted BATs in response to seven peanut extract (PE) concentrations (0.01-10,000 ng/mL) and four control conditions (no stimulant, anti-IgE, fMLP (N-formylmethionine-leucyl-phenylalanine), and anti-FcεRI). We measured avidin binding and CD63 expression on basophils with flow cytometry. We evaluated logistic regression and XGBoost models for peanut allergy classification and feature identification. RESULTS Avidin binding was correlated with CD63 expression. Both markers discriminated between subjects with and without a peanut allergy. Although small by percentage, an avidin+ /CD63- cell subset was found in all allergic subjects tested, indicating that the combination of avidin and CD63 could allow a more comprehensive identification of activated basophils. Indeed, we obtained the best classification accuracy (97.8% sensitivity, 96.7% specificity) by combining avidin and CD63 across seven PE doses. Similar accuracy was obtained by combining PE dose of 10,000 ng/mL for avidin and PE doses of 10 and 100 ng/mL for CD63. CONCLUSIONS Avidin and CD63 are reliable BAT activation markers associated with degranulation. Their combination enhances the identification of activated basophils and improves the classification accuracy of peanut allergy.
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Affiliation(s)
| | - Kaiser Chua
- Department of Mechanical Engineering, Stanford University
| | - Abhinav Kaushik
- Sean N. Parker Center for Allergy and Asthma Research, Stanford University
- Department of Environmental Health, T. H. Chan School of Public Health, Harvard University
| | - Sungu Kim
- Department of Mechanical Engineering, Stanford University
| | - Seth C. Cordts
- Department of Mechanical Engineering, Stanford University
| | - Ceena D. Nafarzadegan
- Sean N. Parker Center for Allergy and Asthma Research, Stanford University
- Department of Microbiology and Immunology, Stanford University
| | | | - Hana Seastedt
- Sean N. Parker Center for Allergy and Asthma Research, Stanford University
| | - Jackson P. Schuetz
- Sean N. Parker Center for Allergy and Asthma Research, Stanford University
| | - Diane Dunham
- Sean N. Parker Center for Allergy and Asthma Research, Stanford University
| | - Ella S. Parsons
- Sean N. Parker Center for Allergy and Asthma Research, Stanford University
| | - Mindy Tsai
- Department of Pathology, Stanford University
| | - Shu Cao
- Sean N. Parker Center for Allergy and Asthma Research, Stanford University
| | - Manisha Desai
- Sean N. Parker Center for Allergy and Asthma Research, Stanford University
- Department of Medicine, Biomedical Informatics Research, Stanford University
| | - Sayantani B. Sindher
- Sean N. Parker Center for Allergy and Asthma Research, Stanford University
- Department of Medicine, Division of Pulmonary, Allergy and Critical Care, Stanford University
| | - R. Sharon Chinthrajah
- Sean N. Parker Center for Allergy and Asthma Research, Stanford University
- Department of Medicine, Division of Pulmonary, Allergy and Critical Care, Stanford University
| | - Stephen J. Galli
- Sean N. Parker Center for Allergy and Asthma Research, Stanford University
- Department of Microbiology and Immunology, Stanford University
- Department of Pathology, Stanford University
| | - Kari C. Nadeau
- Sean N. Parker Center for Allergy and Asthma Research, Stanford University
- Department of Environmental Health, T. H. Chan School of Public Health, Harvard University
| | - Sindy K.Y. Tang
- Department of Mechanical Engineering, Stanford University
- Sean N. Parker Center for Allergy and Asthma Research, Stanford University
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Gertie JA, Zhang B, Liu EG, Hoyt LR, Yin X, Xu L, Long LL, Soldatenko A, Gowthaman U, Williams A, Eisenbarth SC. Oral anaphylaxis to peanut in a mouse model is associated with gut permeability but not with Tlr4 or Dock8 mutations. J Allergy Clin Immunol 2022; 149:262-274. [PMID: 34051223 PMCID: PMC8626534 DOI: 10.1016/j.jaci.2021.05.015] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Revised: 05/06/2021] [Accepted: 05/10/2021] [Indexed: 01/03/2023]
Abstract
BACKGROUND The etiology of food allergy is poorly understood; mouse models are powerful systems to discover immunologic pathways driving allergic disease. C3H/HeJ mice are a widely used model for the study of peanut allergy because, unlike C57BL/6 or BALB/c mice, they are highly susceptible to oral anaphylaxis. However, the immunologic mechanism of this strain's susceptibility is not known. OBJECTIVE We aimed to determine the mechanism underlying the unique susceptibility to anaphylaxis in C3H/HeJ mice. We tested the role of deleterious Toll-like receptor 4 (Tlr4) or dedicator of cytokinesis 8 (Dock8) mutations in this strain because both genes have been associated with food allergy. METHODS We generated C3H/HeJ mice with corrected Dock8 or Tlr4 alleles and sensitized and challenged them with peanut. We then characterized the antibody response to sensitization, anaphylaxis response to both oral and systemic peanut challenge, gut microbiome, and biomarkers of gut permeability. RESULTS In contrast to C3H/HeJ mice, C57BL/6 mice were resistant to anaphylaxis after oral peanut challenge; however, both strains undergo anaphylaxis with intraperitoneal challenge. Restoring Tlr4 or Dock8 function in C3H/HeJ mice did not protect from anaphylaxis. Instead, we discovered enhanced gut permeability resulting in ingested allergens in the bloodstream in C3H/HeJ mice compared to C57BL/6 mice, which correlated with an increased number of goblet cells in the small intestine. CONCLUSIONS Our work highlights the potential importance of gut permeability in driving anaphylaxis to ingested food allergens; it also indicates that genetic loci outside of Tlr4 and Dock8 are responsible for the oral anaphylactic susceptibility of C3H/HeJ mice.
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Affiliation(s)
- Jake A Gertie
- Department of Laboratory Medicine, Yale University School of Medicine, New Haven, Conn; Department of Immunobiology, Yale University School of Medicine, New Haven, Conn
| | - Biyan Zhang
- Department of Laboratory Medicine, Yale University School of Medicine, New Haven, Conn; Department of Immunobiology, Yale University School of Medicine, New Haven, Conn; Singapore Immunology Network (SIgN), Singapore
| | - Elise G Liu
- Department of Laboratory Medicine, Yale University School of Medicine, New Haven, Conn; Department of Immunobiology, Yale University School of Medicine, New Haven, Conn; Section of Rheumatology, Allergy & Immunology, Yale University School of Medicine, New Haven, Conn
| | - Laura R Hoyt
- Department of Laboratory Medicine, Yale University School of Medicine, New Haven, Conn; Department of Immunobiology, Yale University School of Medicine, New Haven, Conn
| | - Xiangyun Yin
- Department of Laboratory Medicine, Yale University School of Medicine, New Haven, Conn; Department of Immunobiology, Yale University School of Medicine, New Haven, Conn
| | - Lan Xu
- Department of Laboratory Medicine, Yale University School of Medicine, New Haven, Conn; Department of Immunobiology, Yale University School of Medicine, New Haven, Conn
| | - Lauren L Long
- The Jackson Laboratory for Genomic Medicine, Farmington, Conn
| | - Arielle Soldatenko
- Department of Laboratory Medicine, Yale University School of Medicine, New Haven, Conn; Department of Immunobiology, Yale University School of Medicine, New Haven, Conn
| | - Uthaman Gowthaman
- Department of Laboratory Medicine, Yale University School of Medicine, New Haven, Conn; Department of Immunobiology, Yale University School of Medicine, New Haven, Conn; Department of Pathology, University of Massachusetts Medical School, Worcester, Mass
| | - Adam Williams
- The Jackson Laboratory for Genomic Medicine, Farmington, Conn; Department of Genetics and Genome Sciences, University of Connecticut Health Center, Farmington, Conn.
| | - Stephanie C Eisenbarth
- Department of Laboratory Medicine, Yale University School of Medicine, New Haven, Conn; Department of Immunobiology, Yale University School of Medicine, New Haven, Conn; Section of Rheumatology, Allergy & Immunology, Yale University School of Medicine, New Haven, Conn.
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Czolk R, Klueber J, Sørensen M, Wilmes P, Codreanu-Morel F, Skov PS, Hilger C, Bindslev-Jensen C, Ollert M, Kuehn A. IgE-Mediated Peanut Allergy: Current and Novel Predictive Biomarkers for Clinical Phenotypes Using Multi-Omics Approaches. Front Immunol 2021; 11:594350. [PMID: 33584660 PMCID: PMC7876438 DOI: 10.3389/fimmu.2020.594350] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Accepted: 12/11/2020] [Indexed: 01/22/2023] Open
Abstract
Food allergy is a collective term for several immune-mediated responses to food. IgE-mediated food allergy is the best-known subtype. The patients present with a marked diversity of clinical profiles including symptomatic manifestations, threshold reactivity and reaction kinetics. In-vitro predictors of these clinical phenotypes are evasive and considered as knowledge gaps in food allergy diagnosis and risk management. Peanut allergy is a relevant disease model where pioneer discoveries were made in diagnosis, immunotherapy and prevention. This review provides an overview on the immune basis for phenotype variations in peanut-allergic individuals, in the light of future patient stratification along emerging omic-areas. Beyond specific IgE-signatures and basophil reactivity profiles with established correlation to clinical outcome, allergenomics, mass spectrometric resolution of peripheral allergen tracing, might be a fundamental approach to understand disease pathophysiology underlying biomarker discovery. Deep immune phenotyping is thought to reveal differential cell responses but also, gene expression and gene methylation profiles (eg, peanut severity genes) are promising areas for biomarker research. Finally, the study of microbiome-host interactions with a focus on the immune system modulation might hold the key to understand tissue-specific responses and symptoms. The immune mechanism underlying acute food-allergic events remains elusive until today. Deciphering this immunological response shall enable to identify novel biomarker for stratification of patients into reaction endotypes. The availability of powerful multi-omics technologies, together with integrated data analysis, network-based approaches and unbiased machine learning holds out the prospect of providing clinically useful biomarkers or biomarker signatures being predictive for reaction phenotypes.
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Affiliation(s)
- Rebecca Czolk
- Department of Infection and Immunity, Luxembourg Institute of Health, Esch-sur-Alzette, Luxembourg
- Faculty of Science, Technology and Medicine, University of Luxembourg, Esch-sur-Alzette, Luxembourg
| | - Julia Klueber
- Department of Infection and Immunity, Luxembourg Institute of Health, Esch-sur-Alzette, Luxembourg
- Department of Dermatology and Allergy Center, Odense Research Center for Anaphylaxis, University of Southern Denmark, Odense, Denmark
| | - Martin Sørensen
- Department of Pediatric and Adolescent Medicine, University Hospital of North Norway, Tromsø, Norway
- Pediatric Research Group, Department of Clinical Medicine, Faculty of Health Sciences, UiT The Arctic University of Norway, Tromsø, Norway
| | - Paul Wilmes
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Esch-sur-Alzette, Luxembourg
| | - Françoise Codreanu-Morel
- Department of Allergology and Immunology, Centre Hospitalier de Luxembourg-Kanner Klinik, Luxembourg, Luxembourg
| | - Per Stahl Skov
- Department of Dermatology and Allergy Center, Odense Research Center for Anaphylaxis, University of Southern Denmark, Odense, Denmark
- RefLab ApS, Copenhagen, Denmark
- Institute of Immunology, National University of Copenhagen, Copenhagen, Denmark
| | - Christiane Hilger
- Department of Infection and Immunity, Luxembourg Institute of Health, Esch-sur-Alzette, Luxembourg
| | - Carsten Bindslev-Jensen
- Department of Dermatology and Allergy Center, Odense Research Center for Anaphylaxis, University of Southern Denmark, Odense, Denmark
| | - Markus Ollert
- Department of Infection and Immunity, Luxembourg Institute of Health, Esch-sur-Alzette, Luxembourg
- Department of Dermatology and Allergy Center, Odense Research Center for Anaphylaxis, University of Southern Denmark, Odense, Denmark
| | - Annette Kuehn
- Department of Infection and Immunity, Luxembourg Institute of Health, Esch-sur-Alzette, Luxembourg
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de Jong GAH, Jayasena S, Johnson P, Marsh J, Apostolovic D, van Hage M, Nordlee J, Baumert J, Taylor SL, Roucairol C, de Jongh H, Koppelman SJ. Purification and Characterization of Naturally Occurring Post-Translationally Cleaved Ara h 6, an Allergen That Contributes Substantially to the Allergenic Potency of Peanut. J Agric Food Chem 2018; 66:10855-10863. [PMID: 30284821 DOI: 10.1021/acs.jafc.8b03140] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The 2S albumin Ara h 6 is one of the most important peanut allergens. A post-translationally cleaved Ara h 6 (pAra h 6) was purified from Virginia type peanuts, and the cleavage site was mapped using high-resolution mass spectrometry. Compared to intact Ara h 6, pAra h 6 lacks a 5-amino acid stretch, resembling amino acids 43-47 (UniProt accession number Q647G9) in the nonstructured loop. Consequently, pAra h 6 consists of two chains: an N-terminal chain of approximately 5 kDa and a C-terminal chain of approximately 9 kDa, held together by disulfide bonds. Intermediate post-translationally cleaved products, in which this stretch is cleaved yet still attached to one of the subunits, are also present. The secondary structure and immunoglobulin E (IgE) binding of pAra h 6 resembles that of intact Ara h 6, indicating that the loss of the nonstructured loop is not critical for maintaining the protein structure. Commercially available monoclonal and polyclonal immunoglobulin G (IgG) antibodies directed to Ara h 6 react with both intact Ara h 6 and pAra h 6, suggesting that the involved epitopes are not located in the area that is post-translationally cleaved. No differences between intact Ara h 6 and pAra h 6 in terms of IgE binding were found, suggesting that the area that is post-translationally cleaved is not involved in IgE epitopes either. For all main cultivars Runner, Virginia, Valencia, and Spanish, intact Ara h 6 and pAra h 6 occur in peanut at similar levels, indicating that pAra h 6 is a consistent and important contributor to the allergenic potency of peanut.
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Affiliation(s)
| | - Shyamali Jayasena
- Food Allergy Research and Resource Program, Department of Food Science & Technology , University of Nebraska , 279 Food Innovation Center , Lincoln , Nebraska 68588-6207 , United States
| | - Phil Johnson
- Food Allergy Research and Resource Program, Department of Food Science & Technology , University of Nebraska , 279 Food Innovation Center , Lincoln , Nebraska 68588-6207 , United States
| | - Justin Marsh
- Food Allergy Research and Resource Program, Department of Food Science & Technology , University of Nebraska , 279 Food Innovation Center , Lincoln , Nebraska 68588-6207 , United States
| | - Danijela Apostolovic
- Immunology and Allergy Unit, Department of Medicine Solna , Karolinska Institutet , 171 77 Stockholm , Sweden
| | - Marianne van Hage
- Immunology and Allergy Unit, Department of Medicine Solna , Karolinska Institutet , 171 77 Stockholm , Sweden
| | - Julie Nordlee
- TNO , Utrechtseweg 48 , 3704 HE , Zeist , The Netherlands
| | - Joe Baumert
- TNO , Utrechtseweg 48 , 3704 HE , Zeist , The Netherlands
| | - Steve L Taylor
- TNO , Utrechtseweg 48 , 3704 HE , Zeist , The Netherlands
| | - Camille Roucairol
- DBV Technologies , Development Department , 92120 Montrouge , France
| | | | - Stef J Koppelman
- Food Allergy Research and Resource Program, Department of Food Science & Technology , University of Nebraska , 279 Food Innovation Center , Lincoln , Nebraska 68588-6207 , United States
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Koppelman SJ, Smits M, Tomassen M, de Jong GAH, Baumert J, Taylor SL, Witkamp R, Veldman RJ, Pieters R, Wichers H. Release of Major Peanut Allergens from Their Matrix under Various pH and Simulated Saliva Conditions-Ara h2 and Ara h6 Are Readily Bio-Accessible. Nutrients 2018; 10:E1281. [PMID: 30208580 PMCID: PMC6165493 DOI: 10.3390/nu10091281] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2018] [Revised: 08/28/2018] [Accepted: 08/31/2018] [Indexed: 01/24/2023] Open
Abstract
The oral mucosa is the first immune tissue that encounters allergens upon ingestion of food. We hypothesized that the bio-accessibility of allergens at this stage may be a key determinant for sensitization. Light roasted peanut flour was suspended at various pH in buffers mimicking saliva. Protein concentrations and allergens profiles were determined in the supernatants. Peanut protein solubility was poor in the pH range between 3 and 6, while at a low pH (1.5) and at moderately high pHs (>8), it increased. In the pH range of saliva, between 6.5 and 8.5, the allergens Ara h2 and Ara h6 were readily released, whereas Ara h1 and Ara h3 were poorly released. Increasing the pH from 6.5 to 8.5 slightly increased the release of Ara h1 and Ara h3, but the recovery remained low (approximately 20%) compared to that of Ara h2 and Ara h6 (approximately 100% and 65%, respectively). This remarkable difference in the extraction kinetics suggests that Ara h2 and Ara h6 are the first allergens an individual is exposed to upon ingestion of peanut-containing food. We conclude that the peanut allergens Ara h2 and Ara h6 are quickly bio-accessible in the mouth, potentially explaining their extraordinary allergenicity.
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Affiliation(s)
- Stef J Koppelman
- Food Allergy Research and Resource Program, Department of Food Science & Technology, University of Nebraska, 279 Food Innovation Center, Lincoln, NE 68588-6207, USA.
| | - Mieke Smits
- Research Group Innovative Testing in Life Sciences and Chemistry, University of Applied Sciences, Heidelberglaan 7, 3584 CS Utrecht, The Netherlands.
| | - Monic Tomassen
- Food & Biobased Research, Wageningen University and Research, Bornse Weilanden 9, P.O. Box 17, 6700 AA Wageningen, The Netherlands.
| | | | - Joe Baumert
- Food Allergy Research and Resource Program, Department of Food Science & Technology, University of Nebraska, 279 Food Innovation Center, Lincoln, NE 68588-6207, USA.
| | - Steve L Taylor
- Food Allergy Research and Resource Program, Department of Food Science & Technology, University of Nebraska, 279 Food Innovation Center, Lincoln, NE 68588-6207, USA.
| | - Renger Witkamp
- Department of Human Nutrition, Wageningen University and Research, Stippeneng 4, 6708 WE Wageningen, The Netherlands.
| | - Robert Jan Veldman
- Research Group Innovative Testing in Life Sciences and Chemistry, University of Applied Sciences, Heidelberglaan 7, 3584 CS Utrecht, The Netherlands.
| | - Raymond Pieters
- Research Group Innovative Testing in Life Sciences and Chemistry, University of Applied Sciences, Heidelberglaan 7, 3584 CS Utrecht, The Netherlands.
- Institute for Risk Assessment Sciences, Faculty of Veterinary Medicines, Utrecht University, Yalelaan 1, 3584 CL, Utrecht, The Netherlands.
| | - Harry Wichers
- Food & Biobased Research, Wageningen University and Research, Bornse Weilanden 9, P.O. Box 17, 6700 AA Wageningen, The Netherlands.
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Tordesillas L, Goswami R, Benedé S, Grishina G, Dunkin D, Järvinen KM, Maleki SJ, Sampson HA, Berin MC. Skin exposure promotes a Th2-dependent sensitization to peanut allergens. J Clin Invest 2014; 124:4965-75. [PMID: 25295541 DOI: 10.1172/jci75660] [Citation(s) in RCA: 150] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2014] [Accepted: 09/04/2014] [Indexed: 01/21/2023] Open
Abstract
Sensitization to foods often occurs in infancy, without a known prior oral exposure, suggesting that alternative exposure routes contribute to food allergy. Here, we tested the hypothesis that peanut proteins activate innate immune pathways in the skin that promote sensitization. We exposed mice to peanut protein extract on undamaged areas of skin and observed that repeated topical exposure to peanut allergens led to sensitization and anaphylaxis upon rechallenge. In mice, this epicutaneous peanut exposure induced sensitization to the peanut components Ara h 1 and Ara h 2, which is also observed in human peanut allergy. Both crude peanut extract and Ara h 2 alone served as adjuvants, as both induced a bystander sensitization that was similar to that induced by the atopic dermatitis-associated staphylococcal enterotoxin B. In cultured human keratinocytes and in murine skin, peanut extract directly induced cytokine expression. Moreover, topical peanut extract application induced an alteration dependent on the IL-33 receptor ST2 in skin-draining DCs, resulting in Th2 cytokine production from T cells. Together, our data support the hypothesis that peanuts are allergenic due to inherent adjuvant activity and suggest that skin exposure to food allergens contributes to sensitization to foods in early life.
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Khan IJ, Di R, Patel P, Nanda V. Evaluating pH-induced gastrointestinal aggregation of Arachis hypogaea 1 fragments as potential components of peanut allergy. J Agric Food Chem 2013; 61:8430-8435. [PMID: 23926999 PMCID: PMC4074858 DOI: 10.1021/jf401701t] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The seed storage glycoprotein Arachis hypogaea (Ara h) 1 is a major allergen found in peanuts. The biochemical resistance of food proteins to protease digestion contributes to their allergenicity. The rapid proteolysis of Ara h 1 under gastric conditions challenges this model. Biophysical and in vitro digestion experiments were carried out to identify how Ara h 1 epitopes might survive digestion, despite their facile degradation. The bicupin core of Ara h 1 can be unfolded at low pH and reversibly folded at higher pH. Additionally, peptide fragments from simulated gastric digestion predominantly form noncovalent aggregates when transferred to base. Disulfide cross-links within these aggregates occur as intermediates in relatively low amounts only at early times and play no role in shielding peptides from degradation. It is proposed that peptide fragments which survive gastric conditions form large aggregates in basic environments such as the small intestine, making epitopes available for triggering an allergic response.
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Affiliation(s)
- I. John Khan
- Center for Advanced Biotechnology and Medicine, Department of Biochemistry and Molecular Biology, Robert Wood Johnson Medical School, University of Medicine and Dentistry of New Jersey, 679 Hoes Lane, Piscataway, NJ 08854, USA
| | - Rong Di
- Department of Plant Biology and Pathology, School of Environmental and Biological Sciences, Rutgers, The State University of New Jersey, 59 Dudley Road, New Brunswick, NJ 08901, USA
| | - Priyesh Patel
- Center for Advanced Biotechnology and Medicine, Department of Biochemistry and Molecular Biology, Robert Wood Johnson Medical School, University of Medicine and Dentistry of New Jersey, 679 Hoes Lane, Piscataway, NJ 08854, USA
| | - Vikas Nanda
- Center for Advanced Biotechnology and Medicine, Department of Biochemistry and Molecular Biology, Robert Wood Johnson Medical School, University of Medicine and Dentistry of New Jersey, 679 Hoes Lane, Piscataway, NJ 08854, USA
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Dirks CG, Pedersen MH, Platzer MH, Bindslev-Jensen C, Skov PS, Poulsen LK. Does absorption across the buccal mucosa explain early onset of food-induced allergic systemic reactions? J Allergy Clin Immunol 2005; 115:1321-3. [PMID: 15940158 DOI: 10.1016/j.jaci.2005.03.027] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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