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1.
Food Chem ; 302: 125350, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31415999

RESUMO

The aim of the study was to investigate the use of serine protease from Yarrowia lipolytica yeast for reduction of milk proteins allergenicity. Whey protein concentrate (WPC-80), αs-casein and their hydrolysates were analyzed for the capacity to bind IgE and IgG antibodies present in sera from patients with cow milk protein allergy using a competitive ELISA. The hydrolysis of αs-casein and whey protein concentrate contributed to a significant reduction of their immunoreactive epitopes. In case of IgE antibodies, the lowest binding capacity was detected in the 24 h hydrolysates of both proteins in which the inhibition of the reaction was ≤20 and ≤68% for αs-casein and whey protein concentrate respectively. One hour hydrolysis of WPC-80 reduced the protein antigenicity, while the longer time (5 h) might lead to the exposure of new IgE - reactive epitopes.


Assuntos
Hipersensibilidade a Leite/imunologia , Proteínas do Leite/imunologia , Hidrolisados de Proteína/imunologia , Serina Proteases/metabolismo , Alérgenos/imunologia , Alérgenos/metabolismo , Animais , Caseínas/imunologia , Caseínas/metabolismo , Pré-Escolar , Ensaio de Imunoadsorção Enzimática , Epitopos , Feminino , Cabras/imunologia , Humanos , Imunoglobulina E/imunologia , Imunoglobulina E/metabolismo , Imunoglobulina G/imunologia , Imunoglobulina G/metabolismo , Proteínas do Leite/metabolismo , Hidrolisados de Proteína/metabolismo , Proteínas do Soro do Leite/imunologia , Proteínas do Soro do Leite/metabolismo , Yarrowia/enzimologia
2.
Food Chem ; 302: 125348, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31442704

RESUMO

Tropomyosin (TM) is the main allergen of shrimp. Glycation reportedly reduced the allergenicity of TM, and the allergenicity reduction was heavily dependent upon the sources of saccharides. In this work we investigated, how glycation of tropomyosin by functional oligosaccharides affected the allergenicity. Compared to TM, the TM glycated by galacto-oligosaccharide (TM-GOS), mannan-oligosaccharide (TM-MOS) and maltopentaose (TM-MPS) had lower allergenicity and induced weaker mouse allergy responses. While the TM glycated by fructo-oligosaccharide (TM-FOS) had stronger allergenicity and induced severe mouse allergy symptoms, due to the generation of neoallergns that belonged to advanced glycation end products (e.g. CML). Therefore, GOS, MOS and MPS could be applied to desensitize shrimp TM-induced food allergy through glycation, while FOS was not suitable to reduce TM allergenicity. Glycation of TM by GOS, MOS and MPS, especially for MPS, significantly reduced allergenicity and alleviated allergy symptoms, which could be potentially explored for immunotherapy for shrimp-allergic patients.


Assuntos
Hipersensibilidade Alimentar/imunologia , Produtos Finais de Glicação Avançada/metabolismo , Palaemonidae/imunologia , Proteínas de Frutos do Mar/metabolismo , Tropomiosina/metabolismo , Adulto , Alérgenos/imunologia , Alérgenos/metabolismo , Animais , Pré-Escolar , Feminino , Hipersensibilidade Alimentar/sangue , Glicosilação , Humanos , Masculino , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade , Oligossacarídeos/imunologia , Oligossacarídeos/metabolismo , Proteínas de Frutos do Mar/química , Proteínas de Frutos do Mar/imunologia , Tropomiosina/química , Tropomiosina/imunologia
3.
Food Chem ; 302: 125333, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31416005

RESUMO

This study was performed to determine Parvalbumin (PV), a well-known fish allergenic protein, digestion kinetics and immunoreactivity of digestion products with Immunoglobulin G/Immunoglobulin E recognition to understand its allergic potential with or without lipid emulsion process. PV was subjected to simulated gastrointestinal digestion in emulsified condition. Digestion kinetics of the protein was analysed by electrophoresis, IgG/IgE binding ability by immunoblotting and indirect ELISA. Lipid emulsion significantly (p < 0.01) reduced the degree of PV hydrolysis by 52.10% for gastric digestion. Immune fragments of gastric digestion were detectable for 90-120 min longer in emulsified condition showing resistance. Consequently, lipid emulsion decreased the digestive ability of PV in stomach, increasing resistance to gastrointestinal digestion by pepsin proteases. It also altered IgG/IgE binding ability of digestion products, thereby indicating that PV with lipid emulsion was resistant to digestion and possessed increased IgE binding ability resulting in higher risk of allergy among sensitized individuals.


Assuntos
Alérgenos/farmacocinética , Emulsões/farmacocinética , Proteínas de Peixes da Dieta/farmacocinética , Hipersensibilidade Alimentar/imunologia , Parvalbuminas/farmacocinética , Alérgenos/imunologia , Alérgenos/metabolismo , Animais , Digestão , Emulsões/química , Ensaio de Imunoadsorção Enzimática , Feminino , Proteínas de Peixes da Dieta/imunologia , Linguados , Hipersensibilidade Alimentar/etiologia , Immunoblotting , Imunoglobulina E/imunologia , Imunoglobulina E/metabolismo , Imunoglobulina G/imunologia , Imunoglobulina G/metabolismo , Lipídeos/química , Lipídeos/farmacocinética , Camundongos Endogâmicos BALB C , Parvalbuminas/imunologia , Parvalbuminas/metabolismo , Pepsina A/metabolismo
4.
Food Chem ; 302: 125186, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31400700

RESUMO

Enzymatic processing could reduce the allergenicity of peanut proteins while may lose the functional properties. Transglutaminase (TGase) is an enzyme for improving the functional properties of proteins/hydrolysates. No studies have been conducted on peanut hydrolysates that are crosslinked with TGase. In this study, allergenicity and functional properties of peanut protein hydrolysate cross-linked by TGase were tested. Papain, ficin and bromelain were selected out of eight food-grade enzymes for the kinetic analysis of peanut protein hydrolysis that lead to high reduction rate (K) of the IgE-binding property. Peanuts hydrolyzed by the three selected enzymes (200 AzU/g) were used for IgE binding, TGase-crosslinking and functional property characterization. After hydrolysis, the IgE-binding properties of the peanut soluble extracts were decreased (by 85%-95%); and functional properties were also decreased as compared to intact peanut protein extracts. The TGase crosslinked hydrolysates had similar IgE-binding properties to the un-crosslinked hydrolysates, but with higher functional properties.


Assuntos
Alérgenos/metabolismo , Arachis/imunologia , Proteínas de Plantas/metabolismo , Transglutaminases/metabolismo , Alérgenos/imunologia , Humanos , Hidrólise , Imunoglobulina E/metabolismo , Cinética , Proteínas de Plantas/imunologia
5.
Ther Umsch ; 76(6): 293-299, 2019 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-31762417

RESUMO

Allergy assessment: when and how? Abstract. Allergies are common in the clinical practice. The most important allergens are pollen, house dust mites, animal dander, mold and allergens attributable to a particular work environment. The medical history is a very important part for diagnosing an allergy, because sensitizations detected by skin prick tests and laboratory tests are common but not always symptomatic and therefore without clinical relevance. There are 3 options to manage allergic diseases: avoidance of allergens, symptomatic treatment and - in selected cases - a causal treatment like allergen-specific immunotherapy.


Assuntos
Alérgenos/imunologia , Hipersensibilidade , Antígenos de Dermatophagoides , Reações Cruzadas , Humanos , Hipersensibilidade/diagnóstico , Testes Cutâneos/métodos
6.
J Agric Food Chem ; 67(45): 12547-12557, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31613616

RESUMO

This study aims at understanding the changes in the structural properties of Gly m 4 soy allergen as a result of the influence of the temperature and pressure deviations. The primary emphasis was placed on analyzing the surface properties of suspected linear and conformational epitopes present in the Gly m 4 allergen. All three epitopes of Gly m 4 were studied, and the results showed that the molecule has significant structural changes in terms of solvent-accessible surface area (SASA) and radius of gyration, which showed that the increased pressures resulted in compaction. However, at lower temperatures and higher pressures (300 K and 6 kbar), swelling in the molecule was observed with a significant increase in the surface area. The study also tracked the changes in surface areas of individual residues that are part of the selected epitopes. Residues, such as D-27 and T-51, were found to have significant changes in their SASA as a result of temperature and pressure deviations.


Assuntos
Alérgenos/química , Antígenos de Plantas/química , Soja/imunologia , Alérgenos/imunologia , Antígenos de Plantas/imunologia , Mapeamento de Epitopos , Modelos Moleculares , Pressão , Soja/química , Temperatura Ambiente
7.
Int J Nanomedicine ; 14: 7053-7064, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31564865

RESUMO

Background: Food allergy (FA) is a significant public health problem. The therapeutic efficacy for FA is unsatisfactory currently. The breakdown of intestinal immune tolerance is associated with the pathogenesis of FA. Therefore, it is of great significance to develop novel therapeutic methods to restore immune tolerance in treating FA. Methods: We proposed an oral administration strategy to treat FA by co-delivering food allergen epitope fragment (peptide: IK) and adjuvant R848 (TLR7 ligand) in the mPEG-PDLLA nanoparticles (PPLA-IK/R848 NPs). The generation of tolerogenic dendritic cells (DCs) and regulatory T cells (Tregs) induced by PPLA-IK/R848 NPs were evaluated in vitro and in vivo. The therapeutic effects of PPLA-IK/R848 NPs were also assessed in an OVA-induced FA model. Results: PPLA-IK/R848 NPs could efficiently deliver IK to DCs to drive DCs into the tolerogenic phenotypes and promote the differentiation of Tregs in vitro and in vivo, significantly inhibited FA responses through the recovery of intestinal immune tolerance. Conclusion: Oral administration of PPLA-IK/R848 NPs could efficiently deliver IK and R848 to intestinal DCs and stimulate DCs into allergen tolerogenic phenotype. These tolerogenic DCs could promote the differentiation of Tregs, which significantly protected mice from food allergic responses. This study provided an efficient formulation to alleviate FA through the recovery of immune tolerance.


Assuntos
Alérgenos/imunologia , Células Dendríticas/imunologia , Sistemas de Liberação de Medicamentos , Epitopos/imunologia , Hipersensibilidade Alimentar/tratamento farmacológico , Hipersensibilidade Alimentar/imunologia , Imidazóis/administração & dosagem , Imidazóis/uso terapêutico , Tolerância Imunológica , Linfócitos T Reguladores/imunologia , Sequência de Aminoácidos , Animais , Diferenciação Celular , Células Dendríticas/efeitos dos fármacos , Imidazóis/química , Imidazóis/farmacologia , Tolerância Imunológica/efeitos dos fármacos , Camundongos Endogâmicos BALB C , Peptídeos/química , Poliésteres/química , Polietilenoglicóis/química , Linfócitos T Reguladores/efeitos dos fármacos
8.
J Agric Food Chem ; 67(37): 10458-10469, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31469568

RESUMO

Mud crab (Scylla paramamosain) is a commonly consumed seafood as a result of its high nutritional value; however, it is associated with food allergy. The current understanding of crab allergens remains insufficient. In the present study, an 18 kDa protein was purified from crab muscle and confirmed to be myosin light chain 1 (MLC1) by matrix-assisted laser desorption/ionization-tandem time-of-flight mass spectrometry. Total RNA was isolated and amplified to obtain a MLC1 open reading frame of 462 bp, encoding 154 amino acids. A structural analysis revealed that recombinant MLC1 (rMLC1) expressed in Escherichia coli contained α-helix and random coil. Moreover, rMLC1 displayed strong immunoactivity by dot blot and a basophil activation test. Furthermore, seven allergenic epitopes of MLC1 were predicted, and five critical epitope regions were identified by an inhibition enzyme-linked immunosorbent assay and human mast cell degranulation assay. This comprehensive research of an allergen helps to conduct component-resolved diagnoses and immunotherapies related to crab allergies.


Assuntos
Alérgenos/imunologia , Proteínas de Artrópodes/imunologia , Braquiúros/genética , Clonagem Molecular , Epitopos/imunologia , Cadeias Leves de Miosina/imunologia , Alérgenos/química , Alérgenos/genética , Sequência de Aminoácidos , Animais , Proteínas de Artrópodes/química , Proteínas de Artrópodes/genética , Braquiúros/química , Braquiúros/imunologia , Degranulação Celular , Epitopos/química , Epitopos/genética , Humanos , Mastócitos/imunologia , Cadeias Leves de Miosina/química , Cadeias Leves de Miosina/genética , Fases de Leitura Aberta , Alinhamento de Sequência
9.
Orv Hetil ; 160(33): 1311-1318, 2019 Aug.
Artigo em Húngaro | MEDLINE | ID: mdl-31401863

RESUMO

Introduction and aim: The aim of our research is to evaluate and compare commonly performed diagnostic tests, and to examine the psychological disorders induced by this food allergy. Children with symptoms suggesting cow's milk protein allergy were included in this study (n = 47). Blood and saliva samples were collected from the participants. Parents were asked to fill in a questionnaire constructed by the research team (containing the DSM-5 symptoms checklist about attention deficit hyperactivity disorder). Method: One of the most widely used diagnostic tool is the skin allergy test, which was performed in 47 subjects (n = 47, mean age: 7.36 years); only 2 children showed positive test result for cow's milk. Lymphocyte transformation test was observed to be positive in 8 children (17%), 4 subjects demonstrated questionable results. In our sub-study about psychological symptoms (n = 43, mean age: 7.88 years), the score was according to the attention deficit hyperactivity disorder symptom checklist before the diet (6.88, SD: 4.43) and showed significant decrease after 3 months of the elimination diet (4.48, SD: 3.69, p = 0.001). Scores of children with sleep disorder (10.62, SD: 4.23) also represented a significant reduction after 3 months of the diet (6.69, SD: 4.59, p = 0.009). Salivary cortisol levels did not show significant changes before and after elimination diet. Results: According to our data, skin allergy testing and lymphocyte transformation test are not reliable diagnostic tools for establishing the diagnosis. Conclusion: We conclude that a significant improvement in clinical symptoms can only be achieved with a strict elimination diet. Orv Hetil. 2019; 160(33): 1311-1318.


Assuntos
Alérgenos/imunologia , Imunoglobulina E/imunologia , Hipersensibilidade a Leite/diagnóstico , Hipersensibilidade a Leite/imunologia , Proteínas do Leite/efeitos adversos , Animais , Bovinos , Criança , Pré-Escolar , Feminino , Hipersensibilidade Alimentar , Humanos , Imunoglobulina E/sangue , Lactente , Recém-Nascido , Masculino , Proteínas do Leite/imunologia , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Testes Cutâneos/métodos
10.
J Sci Food Agric ; 99(15): 6841-6849, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31385312

RESUMO

BACKGROUND: This study aimed to investigate the reduction in the potential allergenicity of soymilk, and its rheological properties, after fermentation with Lactobacillus. Soymilk (SM) was fermented with Lactobacillus brevis and Lactobacillus sp. The molecular weight of fermented soymilk (FSM) was characterized using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and the potential allergenicity of FSM was analyzed using enzyme-linked immunosorbent assay in vitro and the BALB/c mouse model to detect changes in histamine, mouse mast cell protease-1 (mMCP-1), allergen-specific IgG/IgE, and cytokine levels and histomorphology of jejunum in vivo. RESULTS: The SDS-PAGE and enzyme linked immunosorbent assay (ELISA) showed that allergens of soybean (ß-conglycinin and acidic subunit of glycinin) were almost degraded, and their immunoreactivity was decreased. In the BALB/c mouse model, the FSM group did not show anaphylactic shock symptoms compared with the SM group. Moreover, a tendency toward decreased serum allergen-specific IgG/IgE levels, plasma histamine levels, and mMCP-1 concentrations was observed in the FSM group. Furthermore, Th2-related cytokines were decreased, while IFN-γ production increased in spleen cell cultures. The intestinal villus was slightly damaged after the challenge. All these findings indicated that the Th1/Th2 balance in the FSM group shifted toward a Th1 response, ultimately reducing the potential allergenicity of FSM. Rheological assessment suggested that FSM has good viscous and pseudoplastic properties. CONCLUSION: Fermentation might be a promising method for producing tasty, hypoallergenic soybean products. © 2019 Society of Chemical Industry.


Assuntos
Alérgenos/metabolismo , Hipersensibilidade Alimentar/imunologia , Lactobacillus/metabolismo , Proteínas de Soja/imunologia , Soja/imunologia , Soja/microbiologia , Alérgenos/química , Alérgenos/imunologia , Animais , Biotransformação , Manipulação de Alimentos , Humanos , Imunoglobulina E/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Reologia , Leite de Soja/química , Proteínas de Soja/metabolismo , Soja/química , Soja/metabolismo , Células Th1/imunologia , Células Th2/imunologia
11.
Int Arch Allergy Immunol ; 180(2): 144-149, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31256165

RESUMO

BACKGROUND: Several foreign studies have shown long-term efficacy of sublingual immunotherapy (SLIT), but data on the long-term efficacy of SLIT in China are still lacking. OBJECTIVE: We aimed to prospectively evaluate the long-term efficacy of a 2-year SLIT with Dermatophagoides farinae(D. farinae) drops in mono- and polysensitized children with allergic rhinitis (AR). METHODS: Eighty house dust mite (HDM)-sensitized children (aged 4-11 years) with AR were enrolled in this prospective study. There were 40 children in both the monosensitized (to HDM only) and polysensitized groups. Both groups were treated with standardized SLIT (D. farinae drops) for 2 years, combined with pharmacotherapy according to their individual requirements, and were followed up for 7 years. A combined symptom and medication score (CSMS) was assessed and compared between the 2 groups during and after SLIT. Safety was evaluated based on adverse events (AEs). RESULTS: There were 31 (77.5%) monosensitized and 29 (72.5%) polysensitized children who completed the study. After 2-year SLIT, the CSMS of 2 groups significantly decreased compared to baseline. The improvement persisted during the first 5 years at each visit, with a significant difference (all p < 0.01). In the monosensitized group, the CSMS significantly increased during the 6th and the 7th year compared to year 2 (both p < 0.05). Meanwhile, the polysensitized group showed a significant worsening of CSMS from the 5th to the 7th year (all p < 0.05). Furthermore, there was a statistical difference between the 2 groups in the 5th year of the study (p < 0.05). No severe AEs were reported. CONCLUSIONS: The study confirmed the long-term effects which lasted for 7 years after 2-year SLIT in mono- and polysensitized children. Compared with the polysensitized children, the monosensitized children noted a more sustained benefit.


Assuntos
Antígenos de Dermatophagoides/administração & dosagem , Antígenos de Dermatophagoides/imunologia , Dermatophagoides farinae/imunologia , Rinite Alérgica/terapia , Imunoterapia Sublingual/métodos , Administração Sublingual , Alérgenos/administração & dosagem , Alérgenos/imunologia , Animais , Criança , Pré-Escolar , China , Feminino , Humanos , Masculino , Estudos Prospectivos , Imunoterapia Sublingual/efeitos adversos , Resultado do Tratamento
12.
J Agric Food Chem ; 67(31): 8626-8631, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31287307

RESUMO

An almond allergen with two known short peptide sequences was reported as the almond 2S albumin but was later suspected to be almond vicilin. However, this allergen was not designated by the World Health Organization/International Union of Immunological Societies. This study aimed to determine the true identity of this elusive almond allergen. cDNAs were synthesized from total RNA of the Nonpareil almond. The complete sequence of the previously reported almond allergen was determined from its coding sequence. The deduced protein was produced recombinantly and was confirmed to be a food allergen by testing with 18 almond-allergic sera. The allergen is a potential cysteine-rich antimicrobial protein with characteristic C[X]3C-[X]10-12-C[X]3C motifs of the hairpinin antimicrobial protein. This first member of a novel family of food allergens was named Pru du 8. The signature motif of the hairpinin antimicrobial protein can be found in the N-terminal region of some vicilin allergens (e.g., Ara h 1). It can also be found in the signal peptide of other vicilin allergens (e.g., Car i 2). In many species, however, vicilins do not contain such a motif, indicating that the presence of the signature motifs of the hairpinin antimicrobial protein in vicilins might be a result of translocation during evolution.


Assuntos
Alérgenos/imunologia , Antígenos de Plantas/imunologia , Prunus dulcis/imunologia , Alérgenos/química , Alérgenos/genética , Motivos de Aminoácidos , Sequência de Aminoácidos , Antígenos de Plantas/química , Antígenos de Plantas/genética , DNA Complementar/genética , Hipersensibilidade Alimentar/imunologia , Humanos , Prunus dulcis/química , Prunus dulcis/genética , Proteínas de Armazenamento de Sementes/química , Proteínas de Armazenamento de Sementes/genética , Proteínas de Armazenamento de Sementes/imunologia , Alinhamento de Sequência , Análise de Sequência de DNA
13.
J Agric Food Chem ; 67(31): 8660-8667, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31298531

RESUMO

Soybean allergens in food samples are currently detected in most cases using enzyme-linked immunosorbent assays (ELISAs) based on antibodies raised against bulk soybean proteins or specifically targeting soybean trypsin inhibitor, conglycinin, or glycinin. The various commercial ELISAs lack standardized reference material, and the results are often inaccurate because the antibodies cross-react with proteins from other legumes. Furthermore, the isolation of allergenic proteins involves laborious denaturing extraction conditions. To tackle these challenges, we have developed a novel sandwich ELISA based on monoclonal antibodies raised against the soybean 2S albumin Gly m 8 and a recombinant Gly m 8 reference protein with native-analogous characteristics. The antibodies do not cross-react with other legume proteins, and the extraordinary stability and solubility of Gly m 8 allows it to be extracted even from complex matrices after processing. The Gly m 8 ELISA therefore achieves greater specificity and reproducibility than current ELISA tests.


Assuntos
Albuminas 2S de Plantas/análise , Alérgenos/análise , Ensaio de Imunoadsorção Enzimática/métodos , Fast Foods/análise , Contaminação de Alimentos/análise , Proteínas de Soja/análise , Soja/imunologia , Albuminas 2S de Plantas/imunologia , Alérgenos/imunologia , Anticorpos Monoclonais/análise , Anticorpos Monoclonais/imunologia , Reações Cruzadas , Proteínas de Soja/imunologia , Soja/química
14.
Food Chem Toxicol ; 132: 110656, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31279045

RESUMO

Part of the allergenicity assessment of newly expressed proteins in genetically engineered food crops involves an assessment of potential cross-reactivity with known allergens. Bioinformatic approaches are used to evaluate the amino acid sequence identity or similarity between newly expressed proteins and the sequences of known allergens. To be useful, such approaches must be sensitive to detecting cross-reactive potential, but also capable of excluding low-risk sequences. One difficulty in comparing the effectiveness of different bioinformatic approaches has been the lack of a standardized validation and evaluation method. Here, we propose a standardized method for evaluating the sensitivity of different bioinformatic algorithms using a comprehensive database of known allergen sequences. We combine this with a previously described method for evaluating selectivity using sequences from a crop not known to commonly cause food allergy (e.g. maize) to compare the standard ">35% identity-criterion over sliding-window of ≥80 amino acids" bioinformatic approach with the previously described "one-to-one (1:1) FASTA" similarity approach using an E-value threshold of 1E-9. Results confirm the superiority of the 1:1 FASTA approach for selectively detecting cross-reactive allergens. The validation methods described here can be applied to other algorithms to select even better fit-for-purpose approaches for evaluating cross-reactive risk.


Assuntos
Alérgenos/química , Biologia Computacional/normas , Proteínas de Plantas/química , Algoritmos , Alérgenos/imunologia , Sequência de Aminoácidos , Reações Cruzadas/imunologia , Bases de Dados de Proteínas/estatística & dados numéricos , Proteínas de Plantas/imunologia , Zea mays/química
15.
Parasitol Res ; 118(8): 2353-2359, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31263951

RESUMO

Simulium dermatitis is an IgE-mediated skin reaction in animals and humans caused by the bites of black flies. Although Simulium nigrogilvum has been incriminated as the main human-biting black fly species in Thailand, information on its salivary allergens is lacking. Salivary gland extract of S. nigrogilvum females was subjected to sodium dodecylsulfate-polyacrylamide gel electrophoresis, and the separated components were applied onto nitrocellulose membranes for immunoblotting, which was performed by probing the protein blots with sera from 17 individuals who were allergic to the bites of S. nigrogilvum. IgE-reactive protein bands were characterized further by liquid chromatography-mass spectrometry (LC-MS/MS) analysis. Nine protein bands (79, 42, 32, 25, 24, 22, 15, 13, and 11 kDa) were recognized in the serum of the subjects. Four of the nine protein bands (32, 24, 15, and 11 kDa) showed IgE reactivity in all (100%) of the tested sera, and they were identified as salivary secreted antigen 5-related protein, salivary serine protease, erythema protein, and hypothetical secreted protein, respectively. Three other proteins, salivary serine protease (25 kDa), salivary D7 secreted protein (22 kDa), and hypothetical protein (13 kDa), reacted with > 50% of the sera. The relevance of the identified protein bands as allergens needs to be confirmed by using pure recombinant proteins, either in the in vivo skin prick test or in vitro detection of the specific IgE in the serum samples of allergic subjects. This will be useful for the rational design of component-resolved diagnosis and allergen immunotherapy for the allergy mediated by the bites of black flies.


Assuntos
Mordeduras e Picadas/imunologia , Galectina 3/imunologia , Proteínas de Insetos/química , Glândulas Salivares/química , Simuliidae/fisiologia , Alérgenos/química , Alérgenos/imunologia , Animais , Mordeduras e Picadas/parasitologia , Cromatografia Líquida , Eletroforese em Gel de Poliacrilamida , Feminino , Galectina 3/química , Humanos , Imunoglobulina E/imunologia , Proteínas de Insetos/imunologia , Glândulas Salivares/imunologia , Simuliidae/química , Simuliidae/imunologia , Espectrometria de Massas em Tandem , Tailândia
16.
Food Chem ; 298: 125024, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31261007

RESUMO

We investigated the allergenicity, digestibility and functional properties of whey protein isolate (WPI) after covalent conjugation with chlorogenic acid (CHA). The covalent conjugation of CHA may cause an unfolded protein structure. The WPI-CHA conjugate showed lower IgE binding capacity but higher intestinal digestibility than unmodified WPI. Furthermore, after digestion, the IgE binding capacity of ß-lactoglobulin and α-lactoalbumin was lower in the digested WPI-CHA conjugate than digested WPI. Moreover, the solubility, emulsifying activity, foaming properties and antioxidant capacity of WPI were enhanced by covalent conjugation of CHA. Covalent conjugation with CHA might reduce the allergenicity in vitro of WPI by improving the functional properties of the protein.


Assuntos
Alérgenos/imunologia , Proteínas do Soro do Leite/química , Proteínas do Soro do Leite/imunologia , Alérgenos/química , Ácido Clorogênico/química , Digestão , Emulsões/química , Lactoglobulinas/química , Solubilidade
17.
Afr Health Sci ; 19(1): 1460-1466, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31148973

RESUMO

Background: Persistent antigenic stimulation due to repeated exposure to nickel may lead to chronic inflammation resulting in allergic contact dermatitis (ACD). Objectives: This study was performed to assess nickel induced immune activation among patients sensitized against nickel. Patients and Methods: A total of 35 patients (29 females and 6 males; mean age 36±9 years) with nickel contact dermatitis and 20 patch test negative healthy individuals (14 females and 6 males; mean age 29±7 years) were included in this study. Peripheral blood of patients and controls was incubated with nickel sulfate for 24 hours. Immune activation was assessed by CD69 up-regulation on T lymphocyte sub-sets by flow cytometry. Results: Base line expression of CD69 on CD8+ lymphocytes was higher among patients compared to controls (4.1±1.3%vs2.8±1.1%;p<0.009). There was no difference in proportions of CD±CD69+ cells between patients and controls (3.2±0.9%vs2.3±0.8%). Exposure to nickel induced expression of CD69 on a significantly higher proportion of CD4+ lymphocytes (22.1±6.2%) of the ACD patients compared to controls (2.8±2.5%;p<0.0001). Similarly nickel induced CD69 expression on a higher proportion of CD8+ lymphocytes (18.2±5.3%) from ACD patients compared to the controls (1.9±1.8%;p<0.0006). Conclusion: CD69 molecule appears to be an important regulator of immune response in nickel contact dermatitis.


Assuntos
Antígenos CD/metabolismo , Antígenos de Diferenciação de Linfócitos T/metabolismo , Linfócitos T CD4-Positivos/imunologia , Dermatite Alérgica de Contato/imunologia , Lectinas Tipo C/metabolismo , Níquel/efeitos adversos , Níquel/imunologia , Adulto , Alérgenos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/imunologia , Estudos de Casos e Controles , Dermatite Alérgica de Contato/diagnóstico , Feminino , Citometria de Fluxo , Humanos , Masculino , Pessoa de Meia-Idade , Níquel/farmacologia , Testes do Emplastro , Regulação para Cima , Adulto Jovem
18.
Vet Immunol Immunopathol ; 212: 43-49, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31213251

RESUMO

Canine atopic dermatitis (AD) is a chronic, inflammatory and pruritic allergic skin disease in dogs. House dust mites such as Dermatophagoides farinae are one of the known causative agents for the induction of canine AD worldwide. D. farinae protein Der f 2 is known as an important allergen involved in canine AD and recently, Zen-1 has also been identified as an allergenic protein. There is limited information on the prevalence and role of allergen sensitization to crude D. farinae extract (CDF), Der f 2 and Zen-1 among dogs diagnosed with AD in Malaysia. The aim of this study was to determine the proportion of CDF-, Der f 2- and Zen-1-specific reactive sera among dogs diagnosed with AD in Malaysia using an enzyme-linked immunosorbent assay (ELISA). Serum samples were collected from dogs diagnosed with AD from several veterinary clinics in Malaysia. The canine case records were retrieved and information on signalment, dermatological and non-dermatological histories, clinical presentation, food allergies, and exclusion of ectoparasitic, microbial and fungal skin infections were obtained through a survey form. All serum samples were evaluated to quantify the CDF-, Der f 2- and Zen-1-specific immunoglobulin E (IgE) levels. A total of 24.6%, 48.4% and 29.8% of dogs diagnosed with AD were positive for CDF-, Der f 2- and Zen-1-specific IgE, respectively. These results suggest that CDF-, Der f 2- and Zen-1 are important allergens that can contribute to AD in dogs in Malaysia, and serological testing can be performed to provide additional treatment options involving specific immunotherapies.


Assuntos
Antígenos de Dermatophagoides/imunologia , Proteínas de Artrópodes/imunologia , Dermatite Atópica/veterinária , Doenças do Cão/imunologia , Imunoglobulina E/sangue , Alérgenos/imunologia , Animais , Antígenos de Dermatophagoides/sangue , Proteínas de Artrópodes/sangue , Dermatite Atópica/imunologia , Dermatite Atópica/parasitologia , Dermatophagoides farinae , Doenças do Cão/parasitologia , Cães , Ensaio de Imunoadsorção Enzimática , Hospitais Veterinários , Malásia , Animais de Estimação/imunologia
19.
Mol Immunol ; 112: 330-337, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31247376

RESUMO

Shrimp is one of the predominant causes of food allergy among adults, often presenting with severe reactions. Current in vitro diagnostics are based on quantification of patient specific-IgE (sIgE) to shrimp extract. Tropomyosin is the known major shrimp allergen, but IgE sensitisation to other allergens is poorly characterised. In this study, the binding of IgE to various shrimp allergens, additional to tropomyosin, was investigated using sera from 21 subjects who had clinical reactions to one or more shellfish species. Total shrimp-sIgE was quantified using ImmunoCAP, while allergen-sIgEs were quantified using immunoblotting and mass spectrometry, and immuno-PCR to recombinant shrimp tropomyosin. Sixty-two percent of subjects (13/21) were positive to shrimp by ImmunoCAP. IgE from 43% of subjects (9/21) bound tropomyosin, while an additional 29% of subjects (6/21) demonstrated IgE-binding solely to other shrimp allergens, including sarcoplasmic calcium-binding protein, arginine kinase and hemocyanin. Furthermore, IgE sensitisation to other shrimp allergens was demonstrated in 50% of subjects (4/8) who were ImmunoCAP negative. The lack of standardised shrimp allergens and inadequacy of current extracts for shrimp allergy diagnosis is highlighted by this study. Comprehensive knowledge of less studied allergens and their inclusion in component-resolved diagnostics will improve diagnostic accuracy, benefitting the wider population suffering from shellfish allergy.


Assuntos
Alérgenos/imunologia , Artemia/imunologia , Hipersensibilidade Alimentar/diagnóstico , Hipersensibilidade Alimentar/imunologia , Adulto , Animais , Arginina Quinase/imunologia , Proteínas de Ligação ao Cálcio/imunologia , Feminino , Hemocianinas/imunologia , Humanos , Imunoglobulina E/imunologia , Masculino , Pessoa de Meia-Idade , Alimentos Marinhos , Tropomiosina/imunologia , Adulto Jovem
20.
Mol Immunol ; 112: 347-357, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31254775

RESUMO

Peach and apricot can cause allergic reactions with symptoms ranging from mild to very severe, including anaphylaxis. Sometimes subjects allergic to fruits of the Prunus genus have been reported to be also allergic to rubber latex products. The objective of this study is the characterization of a newly identified peach and apricot protein showing similarities with the allergens Hev b 5 from rubber latex and Man e 5 from manioc. This protein has been named ENEA on the basis of the single letter amino acid code of the first four N-terminal residues of the isolated molecule. It has been found in very variable amounts in different peach cultivars and batches. ENEA was isolated from peach pulp extracts by chromatographic separations and identified by direct protein sequencing. At that time, the full length sequence was available only for the homologous protein of the taxonomically closely related apricot, which was produced as a recombinant molecule in Escherichia coli. The following availability of the full length sequence of peach ENEA revealed a very high identity (97%) with the apricot homolog. Similarly to Hev b 5 and to Man e 5, the structural characterization indicated that ENEA is an intrinsically disordered protein. The immunological properties, investigated by dot blotting, the ABA system and the FABER test, showed that ENEA is recognized by specific IgE of allergic patients. In a selected population of 31 patients reporting allergic reactions to peach fruit and/or IgE positive to Hev b 5, 28 and 27 subjects resulted co-sensitized to rENEA and Hev b 5 in the ABA and ISAC test, respectively. In a random population of 3305 suspected allergic patients, analyzed with the FABER test, 17 of them were sensitized to rENEA and 10 of them were also positive to Hev b 5. In addition, both the natural molecule from peach and the recombinant protein of apricot partially inhibited the IgE binding to Hev b 5. In conclusion, a new peach and apricot IgE-binding protein, cross-reacting with the major latex allergen Hev b 5, has been identified. Its variable concentration in the fruit might explain some occasionally occurring allergic reactions. The apricot molecule has recently been registered by the WHO/IUIS Allergen Nomenclature Sub-Committee with the allergen name Pru ar 5. The recombinant form of apricot ENEA, now available, will contribute to allergy diagnosis.


Assuntos
Antígenos de Plantas/imunologia , Reações Cruzadas/imunologia , Hipersensibilidade ao Látex/imunologia , Látex/imunologia , Proteínas de Plantas/imunologia , Prunus armeniaca/imunologia , Prunus persica/imunologia , Adulto , Idoso , Alérgenos/imunologia , Criança , Feminino , Galectina 3/imunologia , Humanos , Imunoglobulina E/imunologia , Masculino , Pessoa de Meia-Idade , Prunus/imunologia , Proteínas Recombinantes/imunologia , Adulto Jovem
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