1
|
Pomés A, Smith SA, Chruszcz M, Mueller GA, Brackett NF, Chapman MD. Precision engineering for localization, validation, and modification of allergenic epitopes. J Allergy Clin Immunol 2024; 153:560-571. [PMID: 38181840 PMCID: PMC10939758 DOI: 10.1016/j.jaci.2023.12.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Revised: 12/20/2023] [Accepted: 12/29/2023] [Indexed: 01/07/2024]
Abstract
The allergen-IgE interaction is essential for the genesis of allergic responses, yet investigation of the molecular basis of these interactions is in its infancy. Precision engineering has unveiled the molecular features of allergen-antibody interactions at the atomic level. High-resolution technologies, including x-ray crystallography, nuclear magnetic resonance spectroscopy, and cryo-electron microscopy, determine allergen-antibody structures. X-ray crystallography of an allergen-antibody complex localizes in detail amino acid residues and interactions that define the epitope-paratope interface. Multiple structures involving murine IgG mAbs have recently been resolved. The number of amino acids forming the epitope broadly correlates with the epitope area. The production of human IgE mAbs from B cells of allergic subjects is an exciting recent development that has for the first time enabled an actual IgE epitope to be defined. The biologic activity of defined IgE epitopes can be validated in vivo in animal models or by measuring mediator release from engineered basophilic cell lines. Finally, gene-editing approaches using the Clustered Regularly Interspaced Short Palindromic Repeats technology to either remove allergen genes or make targeted epitope engineering at the source are on the horizon. This review presents an overview of the identification and validation of allergenic epitopes by precision engineering.
Collapse
Affiliation(s)
| | - Scott A Smith
- Vanderbilt University Medical Center, Nashville, Tenn
| | | | | | | | | |
Collapse
|
2
|
Bartos A, Majak I, Leszczyńska J. Detection of Bet v 1 Homologous Proteins and Plant Profilins by Indirect ELISA. Methods Mol Biol 2024; 2717:305-310. [PMID: 37737993 DOI: 10.1007/978-1-0716-3453-0_20] [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] [Indexed: 09/23/2023]
Abstract
Allergies are an ever-increasing health problem in developed societies. Cross-allergies caused by panallergens are a particularly difficult issue. Proteins similar to the main birch pollen Bet v 1 allergen and profilin are some of the most common allergens. These proteins have a very conservative structure and are present in many distinct organisms. Hence, the knowledge of their natural occurrence is very important for the prevention of allergic reactions. The immunometric method is the most useful approach for determining these allergens. The requirement of reliability and simplicity is fulfilled by enzyme-linked immunosorbent assay (ELISA). In this chapter, detailed procedures are described for the determination of Bet v 1 homologous proteins and plant profilins with the use of indirect, noncompetitive ELISA.
Collapse
Affiliation(s)
- Adrian Bartos
- Department of Bioinorganic Chemistry, Faculty of Pharmacy, Medical University of Lodz, Lodz, Poland
| | - Iwona Majak
- Institute of Technology and Food Analysis, Faculty of Biotechnology and Food Sciences, Lodz University of Technology, Lodz, Poland
| | - Joanna Leszczyńska
- Institute of Natural Products and Cosmetics, Faculty of Biotechnology and Food Sciences, Lodz University of Technology, Lodz, Poland.
| |
Collapse
|
3
|
Zhang Y, Che H, Li C, Jin T. Food Allergens of Plant Origin. Foods 2023; 12:foods12112232. [PMID: 37297475 DOI: 10.3390/foods12112232] [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: 04/15/2023] [Revised: 05/24/2023] [Accepted: 05/26/2023] [Indexed: 06/12/2023] Open
Abstract
This review presents an update on the physical, chemical, and biological properties of food allergens in plant sources, focusing on the few protein families that contribute to multiple food allergens from different species and protein families recently found to contain food allergens. The structures and structural components of the food allergens in the allergen families may provide further directions for discovering new food allergens. Answers as to what makes some food proteins allergens are still elusive. Factors to be considered in mitigating food allergens include the abundance of the protein in a food, the property of short stretches of the sequence of the protein that may constitute linear IgE binding epitopes, the structural properties of the protein, its stability to heat and digestion, the food matrix the protein is in, and the antimicrobial activity to the microbial flora of the human gastrointestinal tract. Additionally, recent data suggest that widely used techniques for mapping linear IgE binding epitopes need to be improved by incorporating positive controls, and methodologies for mapping conformational IgE binding epitopes need to be developed.
Collapse
Affiliation(s)
- Yuzhu Zhang
- US Department of Agriculture, Agricultural Research Service, Pacific West Area, Western Regional Research Center, 800 Buchanan Street, Albany, CA 94710, USA
| | - Huilian Che
- Key Laboratory of Precision Nutrition and Food Quality, Key Laboratory of Functional Dairy, Ministry of Education, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China
| | - Caiming Li
- US Department of Agriculture, Agricultural Research Service, Pacific West Area, Western Regional Research Center, 800 Buchanan Street, Albany, CA 94710, USA
- School of Food Science and Technology, Jiangnan University, Wuxi 214122, China
- Collaborative Innovation Center of Food Safety and Quality Control, Jiangnan University, Wuxi 214122, China
| | - Tengchuan Jin
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei 230001, China
| |
Collapse
|
4
|
Terán MG, García-Ramírez B, Mares-Mejía I, Ortega E, O’Malley A, Chruszcz M, Rodríguez-Romero A. Molecular Basis of Plant Profilins' Cross-Reactivity. Biomolecules 2023; 13:608. [PMID: 37189355 PMCID: PMC10135586 DOI: 10.3390/biom13040608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 03/14/2023] [Accepted: 03/18/2023] [Indexed: 03/30/2023] Open
Abstract
Profilins are ubiquitous allergens with conserved structural elements. Exposure to profilins from different sources leads to IgE-cross-reactivity and the pollen-latex-food syndrome. Monoclonal antibodies (mAbs) that cross-react with plant profilins and block IgE-profilin interactions are relevant for diagnosis, epitope mapping, and specific immunotherapy. We generated IgGs mAbs, 1B4, and 2D10, against latex profilin (anti-rHev b 8) that inhibit the interaction of IgE and IgG4 antibodies from sera of latex- and maize-allergic patients by 90% and 40%, respectively. In this study, we evaluated 1B4 and 2D10 recognition towards different plant profilins, and mAbs recognition of rZea m 12 mutants by ELISAs. Interestingly, 2D10 highly recognized rArt v 4.0101 and rAmb a 8.0101, and to a lesser extent rBet v 2.0101, and rFra e 2.2, while 1B4 showed recognition for rPhl p 12.0101 and rAmb a 8.0101. We demonstrated that residue D130 at the α-helix 3 in profilins, which is part of the Hev b 8 IgE epitope, is essential for the 2D10 recognition. The structural analysis suggests that the profilins containing E130 (rPhl p 12.0101, rFra e 2.2, and rZea m 12.0105) show less binding with 2D10. The distribution of negative charges on the profilins' surfaces at the α-helices 1 and 3 is relevant for the 2D10 recognition, and that may be relevant to explain profilins' IgE cross-reactivity.
Collapse
Affiliation(s)
- María G. Terán
- Instituto de Química, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico; (M.G.T.); (B.G.-R.); (I.M.-M.)
| | - Benjamín García-Ramírez
- Instituto de Química, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico; (M.G.T.); (B.G.-R.); (I.M.-M.)
| | - Israel Mares-Mejía
- Instituto de Química, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico; (M.G.T.); (B.G.-R.); (I.M.-M.)
| | - Enrique Ortega
- Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad. Universitaria, Coyoacán, Mexico City 04510, Mexico;
| | - Andrea O’Malley
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC 29209, USA; (A.O.); (M.C.)
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824, USA
| | - Maksymilian Chruszcz
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC 29209, USA; (A.O.); (M.C.)
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824, USA
| | - Adela Rodríguez-Romero
- Instituto de Química, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico; (M.G.T.); (B.G.-R.); (I.M.-M.)
| |
Collapse
|
5
|
Smith SA, Chruszcz M, Chapman MD, Pomés A. Human Monoclonal IgE Antibodies-a Major Milestone in Allergy. Curr Allergy Asthma Rep 2023; 23:53-65. [PMID: 36459330 PMCID: PMC9831959 DOI: 10.1007/s11882-022-01055-w] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/14/2022] [Indexed: 12/04/2022]
Abstract
PURPOSE OF REVIEW Bound to its high affinity receptor on mast cells and basophils, the IgE antibody molecule plays an integral role in the allergic reaction. Through interactions with the allergen, it provides the sensitivity and specificity parameters for cell activation and mediator release that produce allergic symptoms. Advancements in human hybridoma technologies allow for the generation and molecular definition of naturally occurring allergen-specific human IgE monoclonal antibodies. RECENT FINDINGS A high-resolution structure of dust mite allergen Der p 2 in complex with Fab of the human IgE mAb 2F10 was recently determined using X-ray crystallography. The structure reveals the fine molecular details of IgE 2F10 binding its 750 Å2 conformational epitope on Der p 2. This review provides an overview of this major milestone in allergy, the first atomic resolution structure of an authentic human IgE epitope. The molecular insights that IgE epitopes provide will allow for structure-based design approaches to the development of novel diagnostics, antibody therapeutics, and immunotherapies.
Collapse
Affiliation(s)
- Scott A Smith
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, 37232, USA.
| | - Maksymilian Chruszcz
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC, 29208, USA
| | | | | |
Collapse
|
6
|
Hofer F, Fischer AL, Kamenik AS, Waibl F, Fernández-Quintero ML, Liedl KR. pH-dependent structural diversity of profilin allergens determines thermal stability. FRONTIERS IN ALLERGY 2022; 3:1007000. [PMID: 36324331 PMCID: PMC9618696 DOI: 10.3389/falgy.2022.1007000] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Accepted: 09/20/2022] [Indexed: 11/05/2022] Open
Abstract
The family of profilin allergens is a common class of proteins found in plants, viruses and various eukaryotes including mammals. Profilins are characterized by an evolutionary conserved structural fold, which is responsible for their cross-reactive nature of Immunoglobulin E (IgE) antibodies. Despite their high overall structural similarity, they exhibit substantial differences in their biophysical properties, such as thermal and pH stability. To understand the origin of these functional differences of Amb a 8, Art v 4 and Bet v 2, we performed constant pH molecular dynamics simulation in combination with Gaussian accelerated MD simulations. Depending on the respective protonation at different pH levels, we find distinct differences in conformational flexibility, which are consistent with experimentally determined melting temperatures. These variations in flexibility are accompanied by ensemble shifts in the conformational landscape and quantified and localized by residue-wise B-factors and dihedral entropies. These findings strengthen the link between flexibility of profilin allergens and their thermal stability. Thus, our results clearly show the importance of considering protonation dependent conformational ensembles in solution to elucidate biophysical differences between these structurally similar allergens.
Collapse
|