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1.
Front Immunol ; 15: 1385101, 2024.
Article in English | MEDLINE | ID: mdl-38725998

ABSTRACT

Background: Immunopathology in food allergy is characterized by an uncontrolled type 2 immune response and specific-IgE production. Recent studies have determined that group 2 innate lymphoid cells (ILC2) participate in the food allergy pathogenic mechanism and their severity. Our objective was to investigate the role of ILC2 in peach-allergic patients due to non-specific lipid transfer protein (Pru p 3) sensitization. Methods: The immune response in peripheral blood mononuclear cells was characterized in lipid transfer protein-allergic patients and healthy controls. We have analyzed the Pru p 3 uptake on ILC2, the expression of costimulatory molecules, and their involvement on the T-cell proliferative response and cytokine production under different experimental conditions: cytokines involved in group 2 innate lymphoid cell activation (IL-33 and IL-25), Pru p 3 as main food allergen, and the combination of both components (IL-33/IL-25+Pru p 3) using cell sorting, EliSpot, flow cytometry, and confocal microscopy. Results: Our results show that Pru p 3 allergen is taken up by group 2 innate lymphoid cells, regulating their costimulatory molecule expression (CD83 and HLA-DR) depending on the presence of Pru p 3 and its combination with IL-33/IL-25. The Pru p 3-stimulated ILC2 induced specific GATA3+Th2 proliferation and cytokine (IL-4, IL-5, and IL-13) production in lipid transfer protein-allergic patients in a cell contact-dependent manner with no changes in Tbet+Th1- and FOXP3+Treg cell differentiation. Conclusions: The results indicate that in lipid transfer protein-allergic patients, the responsible allergen, Pru p 3, interacts with group 2 innate lymphoid cells, promoting a Th2 cell response. Our results might be of interest in vivo, as they show a role of group 2 innate lymphoid cells as antigen-presenting cells, contributing to the development of food allergy. Consequently, group 2 innate lymphoid cells may be considered as potential therapeutic targets.


Subject(s)
Antigens, Plant , Carrier Proteins , Food Hypersensitivity , Immunity, Innate , Humans , Food Hypersensitivity/immunology , Female , Antigens, Plant/immunology , Carrier Proteins/immunology , Male , Adult , Cytokines/metabolism , Lymphocytes/immunology , Lymphocytes/metabolism , Plant Proteins/immunology , Lymphocyte Activation/immunology , Young Adult , Middle Aged
2.
Front Immunol ; 15: 1343024, 2024.
Article in English | MEDLINE | ID: mdl-38784378

ABSTRACT

Background: Around 20% of the population in Northern and Central Europe is affected by birch pollen allergy, with the major birch pollen allergen Bet v 1 as the main elicitor of allergic reactions. Together with its cross-reactive allergens from related trees and foods, Bet v 1 causes an impaired quality of life. Hence, new treatment strategies were elaborated, demonstrating the effectiveness of blocking IgG antibodies on Bet v 1-induced IgE-mediated reactions. A recent study provided evidence for the first time that Bet v 1-specific nanobodies reduce patients´ IgE binding to Bet v 1. In order to increase the potential to outcompete IgE recognition of Bet v 1 and to foster cross-reactivity and cross-protection, we developed Bet v 1-specific nanobody trimers and evaluated their capacity to suppress polyclonal IgE binding to corresponding allergens and allergen-induced basophil degranulation. Methods: Nanobody trimers were engineered by adding isoleucine zippers, thus enabling trimeric formation. Trimers were analyzed for their cross-reactivity, binding kinetics to Bet v 1, and related allergens, and patients' IgE inhibition potential. Finally, their efficacy to prevent basophil degranulation was investigated. Results: Trimers showed enhanced recognition of cross-reactive allergens and increased efficiency to reduce IgE-allergen binding compared to nanobody monomers. Furthermore, trimers displayed slow dissociation rates from allergens and suppressed allergen-induced mediator release. Conclusion: We generated high-affine nanobody trimers that target Bet v 1 and related allergens. Trimers blocked IgE-allergen interaction by competing with IgE for allergen binding. They inhibited IgE-mediated release of biological mediators, demonstrating a promising potential to prevent allergic reactions caused by Bet v 1 and relatives.


Subject(s)
Allergens , Antigens, Plant , Cross Reactions , Immunoglobulin E , Single-Domain Antibodies , Immunoglobulin E/immunology , Immunoglobulin E/metabolism , Humans , Antigens, Plant/immunology , Single-Domain Antibodies/immunology , Cross Reactions/immunology , Allergens/immunology , Basophils/immunology , Basophils/metabolism , Protein Binding , Rhinitis, Allergic, Seasonal/immunology , Protein Multimerization
3.
Int J Mol Sci ; 25(10)2024 May 09.
Article in English | MEDLINE | ID: mdl-38791214

ABSTRACT

Common ragweed pollen allergy has become a health burden worldwide. One of the major allergens in ragweed allergy is Amb a 1, which is responsible for over 90% of the IgE response in ragweed-allergic patients. The major allergen isoform Amb a 1.01 is the most allergenic isoform in ragweed pollen. So far, no recombinant Amb a 1.01 with similar allergenic properties to its natural counterpart (nAmb a 1.01) has been produced. Hence, this study aimed to produce a recombinant Amb a 1.01 with similar properties to the natural isoform for improved ragweed allergy management. Amb a 1.01 was expressed in insect cells using a codon-optimized DNA construct with a removable N-terminal His-Tag (rAmb a 1.01). The recombinant protein was purified by affinity chromatography and physicochemically characterized. The rAmb a 1.01 was compared to nAmb a 1.01 in terms of the IgE binding (enzyme-linked immunosorbent assay (ELISA), immunoblot) and allergenic activity (mediator release assay) in well-characterized ragweed-allergic patients. The rAmb a 1.01 exhibited similar IgE reactivity to nAmb a 1.01 in different IgE-binding assays (i.e., IgE immunoblot, ELISA, quantitative ImmunoCAP inhibition measurements). Furthermore, the rAmb a 1.01 showed comparable dose-dependent allergenic activity to nAmb a 1.01 regarding basophil activation. Overall, the results showed the successful expression of an rAmb a 1.01 with comparable characteristics to the corresponding natural isoform. Our findings provide the basis for an improvement in ragweed allergy research, diagnosis, and immunotherapy.


Subject(s)
Allergens , Ambrosia , Antigens, Plant , Immunoglobulin E , Recombinant Proteins , Humans , Antigens, Plant/immunology , Antigens, Plant/genetics , Antigens, Plant/chemistry , Immunoglobulin E/immunology , Animals , Allergens/immunology , Allergens/genetics , Ambrosia/immunology , Recombinant Proteins/immunology , Recombinant Proteins/genetics , Female , Adult , Plant Proteins/immunology , Plant Proteins/genetics , Plant Proteins/chemistry , Rhinitis, Allergic, Seasonal/immunology , Male , Middle Aged , Plant Extracts/chemistry
4.
Int J Mol Sci ; 25(9)2024 May 02.
Article in English | MEDLINE | ID: mdl-38732184

ABSTRACT

Today, allergies have become a serious problem. PR-10 proteins are clinically relevant allergens that have the ability to bind hydrophobic ligands, which can significantly increase their allergenicity potential. It has been recently shown that not only the birch pollen allergen Bet v 1 but also the alder pollen allergen Aln g 1, might act as a true sensitizer of the immune system. The current investigation is aimed at the further study of the allergenic and structural features of Aln g 1. By using qPCR, we showed that Aln g 1 was able to upregulate alarmins in epithelial cells, playing an important role in sensitization. With the use of CD-spectroscopy and ELISA assays with the sera of allergic patients, we demonstrated that Aln g 1 did not completely restore its structure after thermal denaturation, which led to a decrease in its IgE-binding capacity. Using site-directed mutagenesis, we revealed that the replacement of two residues (Asp27 and Leu30) in the structure of Aln g 1 led to a decrease in its ability to bind to both IgE from sera of allergic patients and lipid ligands. The obtained data open a prospect for the development of hypoallergenic variants of the major alder allergen Aln g 1 for allergen-specific immunotherapy.


Subject(s)
Allergens , Antigens, Plant , Immunoglobulin E , Plant Proteins , Pollen , Humans , Pollen/immunology , Pollen/chemistry , Allergens/immunology , Allergens/chemistry , Antigens, Plant/immunology , Antigens, Plant/chemistry , Immunoglobulin E/immunology , Plant Proteins/immunology , Plant Proteins/chemistry , Alnus/immunology , Alnus/chemistry
5.
J Agric Food Chem ; 72(20): 11694-11705, 2024 May 22.
Article in English | MEDLINE | ID: mdl-38723176

ABSTRACT

The most significant and sensitive antigen protein that causes diarrhea in weaned pigs is soybean 7S globulin. Therefore, identifying the primary target for minimizing intestinal damage brought on by soybean 7S globulin is crucial. MicroRNA (miRNA) is closely related to intestinal epithelium's homeostasis and integrity. However, the change of miRNAs' expression and the function of miRNAs in Soybean 7S globulin injured-IPEC-J2 cells are still unclear. In this study, the miRNAs' expression profile in soybean 7S globulin-treated IPEC-J2 cells was investigated. Fifteen miRNAs were expressed differently. The differentially expressed miRNA target genes are mainly concentrated in signal release, cell connectivity, transcriptional inhibition, and Hedgehog signaling pathway. Notably, we noticed that the most significantly decreased miRNA was ssc-miR-221-5p after soybean 7S globulin treatment. Therefore, we conducted a preliminary study on the mechanisms of ssc-miR-221-5p in soybean 7S globulin-injured IPEC-J2 cells. Our research indicated that ssc-miR-221-5p may inhibit ROS production to alleviate soybean 7S globulin-induced apoptosis and inflammation in IPEC-J2 cells, thus protecting the cellular mechanical barrier, increasing cell proliferation, and improving cell viability. This study provides a theoretical basis for the prevention and control of diarrhea of weaned piglets.


Subject(s)
Apoptosis , Globulins , Glycine max , Intestinal Mucosa , MicroRNAs , Soybean Proteins , Animals , MicroRNAs/genetics , MicroRNAs/metabolism , Swine , Cell Line , Glycine max/genetics , Glycine max/chemistry , Glycine max/metabolism , Intestinal Mucosa/metabolism , Soybean Proteins/genetics , Soybean Proteins/metabolism , Globulins/genetics , Globulins/metabolism , Seed Storage Proteins/genetics , Epithelial Cells/metabolism , Cell Proliferation/drug effects , Cell Survival/drug effects , Antigens, Plant
6.
Food Chem ; 453: 139654, 2024 Sep 30.
Article in English | MEDLINE | ID: mdl-38781899

ABSTRACT

As a natural low-calorie sweetener, Mogroside V (Mog-V) has gradually become one of the alternatives to sucrose with superior health attributes. However, Mog-V will bring unpleasant aftertastes when exceeding a threshold concentration. To investigate the possibility of soy protein isolates (SPIs), namely ß-conglycinin (7S), and glycinin (11S) as flavor-improving agents of Mog-V, the binding mechanism between Mog-V and SPIs was explored through multi-spectroscopy, particle size, zeta potential, and computational simulation. The results of the multi-spectroscopic experiments indicated that Mog-V enhanced the fluorescence of 7S/11S protein in a static mode. The binding affinity of 7S-Mog-V was greater compared with 11S-Mog-V. Particle size and zeta potential analysis revealed that the interaction could promote aggregation of 7S/11S protein with different stability. Furthermore, computational simulations further confirmed that Mog-V could interact with the 7S/11S protein in different ways. This research provides a theoretical foundation for the development and application of SPI to improve the flavor of Mog-V, opening a new avenue for further expanding the market demand for Mog-V.


Subject(s)
Soybean Proteins , Sweetening Agents , Soybean Proteins/chemistry , Soybean Proteins/metabolism , Sweetening Agents/chemistry , Sweetening Agents/metabolism , Globulins/chemistry , Globulins/metabolism , Protein Binding , Antigens, Plant/chemistry , Antigens, Plant/metabolism , Computer Simulation , Seed Storage Proteins/chemistry , Seed Storage Proteins/metabolism , Molecular Docking Simulation , Triterpenes
7.
J Agric Food Chem ; 72(21): 12270-12280, 2024 May 29.
Article in English | MEDLINE | ID: mdl-38743450

ABSTRACT

Allergenicity of soybean 7S protein (7S) troubles many people around the world. However, many processing methods for lowering allergenicity is invalid. Interaction of 7S with phenolic acids, such as chlorogenic acid (CHA), to structurally modify 7S may lower the allergenicity. Hence, the effects of covalent (C-I, periodate oxidation method) and noncovalent interactions (NC-I) of 7S with CHA in different concentrations (0.3, 0.5, and 1.0 mM) on lowering 7S allergenicity were investigated in this study. The results demonstrated that C-I led to higher binding efficiency (C-0.3:28.51 ± 2.13%) than NC-I (N-0.3:22.66 ± 1.75%). The C-I decreased the α-helix content (C-1:21.06%), while the NC-I increased the random coil content (N-1:24.39%). The covalent 7S-CHA complexes of different concentrations had lower IgE binding capacity (C-0.3:37.38 ± 0.61; C-0.5:34.89 ± 0.80; C-1:35.69 ± 0.61%) compared with that of natural 7S (100%), while the noncovalent 7S-CHA complexes showed concentration-dependent inhibition of IgE binding capacity (N-0.3:57.89 ± 1.23; N-0.5:46.91 ± 1.57; N-1:40.79 ± 0.22%). Both interactions produced binding to known linear epitopes. This study provides the theoretical basis for the CHA application in soybean products to lower soybean allergenicity.


Subject(s)
Antigens, Plant , Chlorogenic Acid , Glycine max , Immunoglobulin E , Soybean Proteins , Chlorogenic Acid/chemistry , Chlorogenic Acid/pharmacology , Glycine max/chemistry , Glycine max/immunology , Immunoglobulin E/immunology , Soybean Proteins/chemistry , Soybean Proteins/immunology , Antigens, Plant/chemistry , Antigens, Plant/immunology , Humans , Food Hypersensitivity/immunology , Allergens/chemistry , Allergens/immunology , Protein Binding , Seed Storage Proteins/chemistry , Seed Storage Proteins/immunology
8.
J Agric Food Chem ; 72(17): 9947-9954, 2024 May 01.
Article in English | MEDLINE | ID: mdl-38647139

ABSTRACT

Glycinin is an important allergenic protein. A1a is the acidic chain of the G1 subunit in glycinin (G1A1a), and it has strong allergenicity. In this study, we used phage display technology to express the protein of G1A1a and its overlapping fragments and an indirect enzyme-linked immunosorbent assay (iELISA) to determine the antigenicity and allergenicity of the expressed protein. After three rounds of screening, it was determined that fragment A1a-2-B-I (151SLENQLDQMPRRFYLAGNQEQEFLKYQQEQG181) is the allergenic domain of G1A1a destroyed by thermal processing. In addition, three overlapping peptides were synthesized from fragments A1a-2-B-I, and a linear epitope was found in this domain through methods including dot blot and iELISA. Peptide 2 (157DQMPRRFYLANGNQE170) showed allergenicity, and after replacing it with alanine, it was found that amino acids D157, Q158, M159, and Y164 were the key amino acids that affected its antigenicity, while Q158, M159, R162, and N168 affected allergenicity.


Subject(s)
Allergens , Globulins , Hot Temperature , Soybean Proteins , Allergens/immunology , Allergens/chemistry , Humans , Globulins/chemistry , Globulins/immunology , Soybean Proteins/chemistry , Soybean Proteins/immunology , Amino Acid Sequence , Food Hypersensitivity/immunology , Epitopes/chemistry , Epitopes/immunology , Protein Domains , Antigens, Plant/immunology , Antigens, Plant/chemistry , Antigens, Plant/genetics , Glycine max/chemistry , Glycine max/immunology , Enzyme-Linked Immunosorbent Assay
9.
Int J Biol Macromol ; 269(Pt 1): 131900, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38677675

ABSTRACT

Liposomes were modified with different proportions of ß-conglycinin (7S) and glycinin (11S) to form Lip-7S and Lip-11S. The morphology, interaction and in vitro simulated digestion of liposomes were studied. The particle size of Lip-7S was smaller than that of Lip-11S. When the values of Lip-7S and Lip-11S were 1:1 and 1:0.75, respectively, the ζ-potential had the maximum absolute value and the dispersion of the system was good. The results of multispectral analysis showed that hydrogen-bond and hydrophobic interaction dominated protein-modified liposomes, the protein structure adsorbed on the surface of liposomes changed, the content of α-helix decreased, and the structure of protein-modified liposomes became denser. The surface hydrophobicity and micropolarity of liposomes decreased with the increase of protein ratio, and tended to be stable after Lip-7S (1:1) and Lip-11S (1:0.75). Differential scanning calorimetry showed that Lip-7S had higher phase transition temperature (≥170.5 °C) and better rigid structure. During simulated digestion, Lip-7S (22.5 %) released less Morin than Lip (40.6 %) and Lip-11S (26.2 %), and effectively delayed the release of FFAs. The environmental stability of liposomes was effectively improved by protein modification, and 7S had better modification effect than 11S. This provides a theoretical basis for 7S and 11S modified liposomes, and also provides a data reference for searching for new materials for stabilization of liposomes.


Subject(s)
Antigens, Plant , Globulins , Liposomes , Seed Storage Proteins , Soybean Proteins , Globulins/chemistry , Seed Storage Proteins/chemistry , Soybean Proteins/chemistry , Liposomes/chemistry , Antigens, Plant/chemistry , Hydrophobic and Hydrophilic Interactions , Digestion , Particle Size , Hydrogen Bonding
10.
Rev Alerg Mex ; 71(1): 78, 2024 Feb 01.
Article in Spanish | MEDLINE | ID: mdl-38683095

ABSTRACT

OBJECTIVE: Analyze phylogenetic relationships and molecular mimicry of Cit s 2 and other plant profilins. METHODS: Online bioinformatics tools including Basic Local Alignment Search Tool (BLASTP), PRALINE and MEGA were used for multiple alignments and phylogenetic analysis. A 3D-homology model of Cit s 2 was predicted. Models were calculated with MODELLER. The best model was selected with the model scoring option of MAESTRO. Conserved regions between Cit s 2 and other profilins were located on the 3D model and antigenic regions were predicted by ElliPro server (3-5). RESULTS: Cit s 2 amino acid sequence (Uniprot code:P84177) was compared with other 30 profilins from different allergenic sources. The identity between Cit s 2 and other profilins ranged between 82 and 99%. The highest identity was observed with Cucumis melo (99%) followed by Prunus persica (98%) and Malus domestica (92%). High conserved antigenic regions were observed on the 3D predicted model. Seven lineal and six discontinuous epitopes were found in Cit s 2. CONCLUSION: High conserved antigenic regions were observed on the 3D predicted model of Cit s 2, which might involve potential cross-reactivity between Cit s 2 and other profilins. Future studies are needed to further analyze these results.


OBJETIVO: Analizar las relaciones filogenéticas y el mimetismo molecular de Cit s 2 y otras profilinas vegetales. MÉTODOS: Se utilizaron herramientas bioinformáticas en línea, incluida la de búsqueda de alineación local básica (BLASTP), PRALINE y MEGA, para alineamientos múltiples y análisis filogenético. Se predijo un modelo de homología 3D de Cit s 2. Los modelos se calcularon con MODELLER. El mejor modelo fue seleccionado con la opción de puntuación de modelo de Maestro. Las regiones conservadas entre Cit s 2 y otras profilinas se ubicaron en el modelo 3D y las regiones antigénicas fueron predichas por el servidor ElliPro (3-5). RESULTADOS: La secuencia de aminoácidos de Cit s 2 (código Uniprot: P84177), se comparó con otras 30 profilinas de diferentes fuentes alergénicas. La mayor identidad se observó con Cucumis melo (99%) seguida de Prunus persica (98%) y Malus domestica (92%). Se observaron regiones antigénicas altamente conservadas en el modelo predicho en 3D. Se encontraron siete epítopes lineales, y seis epítopes discontinuos en Cit s 2. CONCLUSIÓN: Se observaron regiones antigénicas altamente conservadas en el modelo 3D predicho de Cit s 2, lo que podría implicar una posible reactividad cruzada entre Cit s 2 y otras profilinas. Se necesitan estudios futuros para analizar más a fondo estos resultados.


Subject(s)
Antigens, Plant , Profilins , Allergens/immunology , Amino Acid Sequence , Computer Simulation , Conserved Sequence , Models, Molecular , Phylogeny , Plant Proteins/immunology , Profilins/immunology , Profilins/genetics , Profilins/chemistry , Cucumis/chemistry , Cucumis/metabolism , Prunus persica/chemistry , Prunus persica/metabolism , Malus/chemistry , Malus/metabolism , Antigens, Plant/chemistry
11.
Anal Chem ; 96(18): 6947-6957, 2024 May 07.
Article in English | MEDLINE | ID: mdl-38656889

ABSTRACT

Life-threatening allergic reactions to food allergens, particularly peanut protein Ara h1, are a growing public health concern affecting millions of people worldwide. Thus, accurate and rapid detection is necessary for allergen labeling and dietary guidance and ultimately preventing allergic incidents. Herein, we present a novel ratiometric fluorescence aptasensor based on multivalent aptamer-encoded DNA flowers (Mul-DNFs) for the high-stability and sensitive detection of allergen Ara h1. The flower-shaped Mul-DNFs were spontaneously packaged using ultralong polymeric DNA amplicons driven by a rolling circle amplification reaction, which contains a large number of Ara h1 specific recognition units and has excellent binding properties. Furthermore, dual-color fluorescence-labeled Mul-DNFs probes were developed by hybridizing them with Cy3- and Cy5-labeled complementary DNA (cDNA) to serve as a ratiometric fluorescence aptasensor platform based on fluorescence resonance energy transfer. Benefiting from the combined merits of the extraordinary synergistic multivalent binding ability of Mul-DNFs, the excellent specificity of the aptamer, and the sensitivity of the ratiometric sensor to avoid exogenous interference. The developed ratiometric aptasensor showed excellent linearity (0.05-2000 ng mL-1) with a limit of detection of 0.02 ng mL-1. Additionally, the developed ratiometric fluorescence aptasensor was utilized for quantifying the presence of Ara h1 in milk, infant milk powder, cookies, bread, and chocolate with recoveries of 95.7-106.3%. The proposed ratiometric aptasensor is expected to be a prospective universal aptasensor platform for the rapid, sensitive, and accurate determination of food and environmental hazards.


Subject(s)
Allergens , Antigens, Plant , Aptamers, Nucleotide , Fluorescence Resonance Energy Transfer , Membrane Proteins , Aptamers, Nucleotide/chemistry , Allergens/analysis , Antigens, Plant/analysis , Biosensing Techniques/methods , DNA/chemistry , Animals , Limit of Detection , Glycoproteins/analysis , Glycoproteins/chemistry , Fluorescent Dyes/chemistry , Plant Proteins/analysis , Plant Proteins/chemistry
12.
J Agric Food Chem ; 72(12): 6601-6612, 2024 Mar 27.
Article in English | MEDLINE | ID: mdl-38480492

ABSTRACT

ß-conglycinin (ß-CG) induces intestinal damage in piglets; however, its regulatory mechanisms are not fully understood. This study aimed to investigate the molecular mechanisms by which ß-CG regulates intestinal injury in piglets through downstream genes and proteins. Our findings revealed that ß-CG significantly reduced villus height while increasing the crypt depth. In addition, we analyzed the transcriptome and proteome of jejunum tissues after the ß-CG treatment. In total, 382 differentially expressed genes (DEGs) and 292 differentially expressed proteins (DEPs) were identified between the treatment and the control groups. The expression levels of DEGs and DEPs were validated by using quantitative reverse transcription polymerase chain reaction (qRT-PCR) and Western blotting, respectively. The findings revealed a consistent correlation between their expression levels and transcriptomic and proteomic data. In addition, Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses of DEGs and DEPs revealed their enrichment in oxidation-related GOs, as well as in lysosome-related pathways. A protein-protein interaction (PPI) regulatory network was constructed based on the DEPs. The integration of transcriptomic and proteomic analyses identified six genes that were significantly different at both the transcript and the protein levels. This study provides valuable insights into the molecular mechanisms underlying ß-CG-induced intestinal injury in piglets.


Subject(s)
Antigens, Plant , Globulins , Proteome , Seed Storage Proteins , Soybean Proteins , Transcriptome , Animals , Swine , Proteomics , Intestines , Gene Expression Profiling
13.
Int J Biol Macromol ; 264(Pt 2): 130613, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38447836

ABSTRACT

The 2S albumins Ara h 2 and Ara h 6 have been shown to be the most important source of allergenicity in peanut. Several isoforms of these allergens have been described. Using extraction and liquid chromatography we isolated proteins with homology to Ara h 2 and characterized hitherto unknown Ara h 2 proteoforms with additional post-translational cleavage. High-resolution mass spectrometry located the cleavage site on the non-structured loop of Ara h 2 while far UV CD spectroscopy showed a comparable structure to Ara h 2. The cleaved forms of Ara h 2 were present in genotypes of peanut commonly consumed. Importantly, we revealed that newly identified Ara h 2 cleaved proteoforms showed comparable IgE-binding using sera from 28 peanut-sensitized individuals, possessed almost the same IgE binding potency and are likely similarly allergenic as intact Ara h 2. This makes these newly identified forms relevant proteoforms of peanut allergen Ara h 2.


Subject(s)
Peanut Hypersensitivity , Plant Proteins , Humans , Plant Proteins/chemistry , Antigens, Plant/chemistry , Immunoglobulin E/metabolism , 2S Albumins, Plant/chemistry , Glycoproteins/chemistry , Allergens/chemistry , Arachis/chemistry
14.
J Agric Food Chem ; 72(11): 5926-5934, 2024 Mar 20.
Article in English | MEDLINE | ID: mdl-38457471

ABSTRACT

Glycinin (11S) and ß-conglycinin (7S) from soybean (glycine max) cause diarrhea and intestinal barrier damage in young animals. Understanding the mechanisms underlying the damage caused by 7S and 11S, it is vital to develop strategies to eliminate allergenicity. Consequently, we investigated 7S/11S-mediated apoptosis in porcine intestinal epithelial (IPEC-J2) cells. IPEC-J2 cells suffered endoplasmic reticulum stress (ERS) in response to 7S and 11S, activating protein kinase RNA-like ER kinase, activating transcription factor 6, C/EBP homologous protein, and inositol-requiring enzyme 1 alpha. 4-Phenylbutyric acid (4-PBA) treatment alleviated ERS; reduced the NLR family pyrin domain containing 3, interleukin-1ß, and interleukin-18 levels; inhibited apoptosis; increased mitofusin 2 expression; and mitigated Ca2+ overload and mitochondria-associated ER membrane (MAM) dysfunction, thereby ameliorating IPEC-J2 injury. We demonstrated the pivotal role of ERS in MAM dysfunction and 7S- and 11S-mediated apoptosis, providing insights into 7S- and 11S-mediated intestinal barrier injury prevention and treatment.


Subject(s)
Antigens, Plant , Apoptosis , Globulins , Glycine max , Phenylbutyrates , Seed Storage Proteins , Soybean Proteins , Animals , Swine , Endoplasmic Reticulum , Mitochondria , Endoplasmic Reticulum Stress
16.
Allergol Immunopathol (Madr) ; 52(2): 48-50, 2024.
Article in English | MEDLINE | ID: mdl-38459890

ABSTRACT

This report is a case of anaphylaxis in an adolescent due to allergy to gibberellin-regulated proteins mediated by cofactors, in probable relation to a pollen/food allergy syndrome. It should also emphasizes the importance of obtaining a faithful clinical history, especially when it comes to adolescent patients as they tend to initiate toxic habits.


Subject(s)
Anaphylaxis , Citrus sinensis , Food Hypersensitivity , Humans , Adolescent , Anaphylaxis/diagnosis , Anaphylaxis/etiology , Gibberellins/adverse effects , Allergens , Antigens, Plant , Food Hypersensitivity/diagnosis
17.
Sci Rep ; 14(1): 5618, 2024 03 07.
Article in English | MEDLINE | ID: mdl-38454094

ABSTRACT

The hazel allergen Cor a 1 is a PR-10 protein, closely related to the major birch pollen allergen Bet v 1. Hazel allergies are caused by cross-reactive IgE antibodies originally directed against Bet v 1. Despite the importance of PR-10 proteins in allergy development, their function and localization in the plant remain largely elusive. Therefore, the presence of Cor a 1 mRNA and proteins was investigated in different tissues, i.e., the female flower, immature and mature nuts, catkins, and pollen. Four yet unknown Cor a 1 isoallergens, i.e., Cor a 1.0501-1.0801, and one new Cor a 1.03 variant were discovered and characterized. Depending on the isoallergen, the occurrence and level of mRNA expression varied in different tissues, suggesting different functions. Interestingly, Cor a 1.04 previously thought to be only present in nuts, was also detected in catkins and pollen. The corresponding Cor a 1 genes were expressed in Escherichia coli. The purified proteins were analysed by CD and NMR spectroscopy. Immunoblots and ELISAs to determine their allergenic potential showed that the new proteins reacted positively with sera from patients allergic to birch, hazel and elder pollen and were recognized as novel isoallergens/variants by the WHO/IUIS Allergen Nomenclature Sub-Committee.


Subject(s)
Corylus , Hypersensitivity , Humans , Aged , Allergens , Plant Proteins/metabolism , Pollen/metabolism , Betulaceae/metabolism , Betula/metabolism , RNA, Messenger , Antigens, Plant/genetics , Antigens, Plant/metabolism
18.
Clin Exp Immunol ; 216(1): 25-35, 2024 03 12.
Article in English | MEDLINE | ID: mdl-38346116

ABSTRACT

In peanut allergy, Arachis hypogaea 2 (Ara h 2) and Arachis hypogaea 6 (Ara h 6) are two clinically relevant peanut allergens with known structural and sequence homology and demonstrated cross-reactivity. We have previously utilized X-ray crystallography and epitope binning to define the epitopes on Ara h 2. We aimed to quantitatively characterize the cross-reactivity between Ara h 2 and Ara h 6 on a molecular level using human monoclonal antibodies (mAbs) and structural characterization of allergenic epitopes. We utilized mAbs cloned from Ara h 2 positive single B cells isolated from peanut-allergic, oral immunotherapy-treated patients to quantitatively analyze cross-reactivity between recombinant Ara h 2 (rAra h 2) and Ara h 6 (rAra h 6) proteins using biolayer interferometry and indirect inhibitory ELISA. Molecular dynamics simulations assessed time-dependent motions and interactions in the antibody-antigen complexes. Three epitopes-conformational epitopes 1.1 and 3, and the sequential epitope KRELRNL/KRELMNL-are conserved between Ara h 2 and Ara h 6, while two more conformational and three sequential epitopes are not. Overall, mAb affinity was significantly lower to rAra h 6 than it was to rAra h 2. This difference in affinity was primarily due to increased dissociation of the antibodies from rAra h 6, a phenomenon explained by the higher conformational flexibility of the Ara h 6-antibody complexes in comparison to Ara h 2-antibody complexes. Our results further elucidate the cross-reactivity of peanut 2S albumins on a molecular level and support the clinical immunodominance of Ara h 2.


Subject(s)
Arachis , Plant Proteins , Humans , Arachis/metabolism , Plant Proteins/chemistry , Plant Proteins/metabolism , Antigens, Plant/chemistry , Antibodies, Monoclonal , 2S Albumins, Plant/chemistry , Immunoglobulin E , Epitopes , Allergens
19.
Clin Exp Allergy ; 54(3): 169-184, 2024 03.
Article in English | MEDLINE | ID: mdl-38423799

ABSTRACT

Randomised controlled trials investigating the efficacy of oral tolerance induction to peanut have enabled detailed comparison of their clinical and immunological success. They have demonstrated that the regular consumption of peanut for at least 2 years by babies who are not allergic enables protection from developing peanut allergy. The LEAP study intervention tested the impact of regular peanut consumption for 4 years and demonstrated a sustained protection against the development of peanut allergy even after 12 months of peanut avoidance from 5 to 6 years of age. The PreventADALL trial introduced multiple allergens into babies' diets from early infancy and reduced the prevalence of food allergy at 3 years, especially by protecting against peanut allergy. Immunological studies from the LEAP cohort demonstrated that regular peanut consumption was associated with a prompt induction of peanut-specific IgG4 and reduced manufacture of peanut and Ara h 2-specific IgE. Even after stopping peanut consumption for 5 years, there continued to be a significant fall in peanut-specific Ara h 2 IgE in the consumption group from 5 to 6 years of age (p < .01). Children who developed peanut allergy by 5 years started to develop increasing sensitisation to linear sequential peanut epitopes from 2.5 years of age, suggesting that putative disease-modifying interventions should commence before 3 years. Data comparing clinical outcomes between children undergoing peanut immunotherapy from infancy suggest that younger children can consume higher portions of peanut without reaction on challenge whilst taking immunotherapy, have fewer side effects and are more likely to enjoy remission of PA. Peanut oral immunotherapy modulates T-cell populations in order to bring about hypo-responsiveness of allergy effector cells. Studies are now needed to characterise and compare different states of immunological tolerance. This will accelerate the design of interventions which can promote primary, secondary and tertiary levels of PA prevention across a range of age groups.


Subject(s)
Food Hypersensitivity , Peanut Hypersensitivity , Child , Infant , Humans , Child, Preschool , Peanut Hypersensitivity/prevention & control , Immunoglobulin E , Epitopes , Arachis , Allergens , Antigens, Plant
20.
Food Chem ; 445: 138707, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38354644

ABSTRACT

The pH-shifting process is an effective encapsulation method, and it is typically performed at extreme alkaline pH, which severely limits the application. In this study, we found that there were critical pH for the unfolding proteins during pH-shifting from 7 to 12, and upon the critical pH, physiochemical characteristics of protein greatly changed, leading to a sharp increase of encapsulation of hydrophobic actives. Firstly, the critical pH for ß-conglycinin (7S) or Glycinin (11S) unfolding was determined by multispectral technology. The critical pH for 7S and 11S were 10.5 and 10.3, respectively. The encapsulation efficiency (EE) obtained by ß-conglycinin-curcumin nanocomposite (7S-Cur) (88.80 %) and Glycinin-curcumin nanocomposite (11S-Cur) (88.38 %) at critical pH was significantly higher than that obtained by pH 7 (7S-Cur = 16.66 % and 11S-Cur = 15.78 %), and both values were close to EE obtained by at 12 (7S-Cur = 95.16 % and 11S-Cur = 94.63 %). The large-scale application of hydrophobic functional compounds will be enhanced by the experimental results.


Subject(s)
Curcumin , Globulins , Soybean Proteins/chemistry , Antigens, Plant/chemistry , Seed Storage Proteins/chemistry , Globulins/chemistry , Hydrophobic and Hydrophilic Interactions , Hydrogen-Ion Concentration
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