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Cells Sep 2019Food allergies associated with class E immunoglobulins (IgE) are a serious health problem that affects between 1% and 10% of the population of developing countries, with... (Review)
Review
Food allergies associated with class E immunoglobulins (IgE) are a serious health problem that affects between 1% and 10% of the population of developing countries, with a variability that depends on the geographical area and age range considered. These allergies are caused by a cross-link reaction between a specific food protein (the allergen) and the host IgE. Allergic reactions can range from mild itching to anaphylactic shock and there are no clues to predict the effects of an allergen. Strict avoidance of allergenic food is the only way to avoid possible serious allergic reactions. In the last 30 years a growing number of molecular studies have been conducted to obtain information on the diffusion of food allergens and to establish the structural basis of their allergenicity. At the same time, these studies have also allowed the development of molecular tools (mainly based on synthetic peptides and recombinant allergens) that can be of great help for diagnostic and therapeutic approaches of food allergies. Accordingly, this review focuses on advances in the study of food allergens made possible by molecular technologies and how results and technologies can be integrated for the development of a systematic food molecular allergology. The review may be of interest both to scientists approaching this field of investigation and to physicians who wish to have an update on the progress of research in diagnosis and therapy of food allergies.
Topics: Allergens; Food Hypersensitivity; Humans; Immunoglobulin E; Immunotherapy; Molecular Biology
PubMed: 31547388
DOI: 10.3390/cells8091073 -
Allergology International : Official... Jul 2021Pollen from many tree species in the Cupressaceae family is a well-known cause of seasonal allergic diseases worldwide. Japanese cedar pollinosis and Japanese cypress... (Review)
Review
Pollen from many tree species in the Cupressaceae family is a well-known cause of seasonal allergic diseases worldwide. Japanese cedar pollinosis and Japanese cypress pollinosis, which are caused by pollen from Japanese cedar (Cryptomeria japonica) and Japanese cypress (Chamaecyparis obtusa), respectively, are the most prevalent seasonal allergic diseases in Japan. Recently, the novel major Japanese cypress allergen Cha o 3 and the homologous Japanese cedar allergen Cry j cellulase were identified, and it was shown, for the first time, that cellulase in plants is allergenic. Although the allergenic components of pollen from both species exhibit high amino acid sequence identity, their pollinosis responded differently to allergen-specific immunotherapy (ASIT) using a standardized extract of Japanese cedar pollen. Pharmacotherapy and ASIT for Japanese cedar and cypress pollinosis have advanced considerably in recent years. In particular, Japanese cedar ASIT has entered a new phase, primarily in response to the generation of updated efficacy data and the development of new formulations. In this review, we focus on both Japanese cypress and cedar pollinosis, and discuss the latest findings, newly identified causative allergens, and new treatments. To manage pollinosis symptoms during spring effectively, ASIT for both Japanese cedar and Japanese cypress pollen is considered necessary.
Topics: Allergens; Cellulase; Chamaecyparis; Cross Reactions; Cryptomeria; Desensitization, Immunologic; Humans; Plant Proteins; Rhinitis, Allergic, Seasonal
PubMed: 33962864
DOI: 10.1016/j.alit.2021.04.002 -
Frontiers in Immunology 2020Allergen immunotherapy is currently the only causal treatment for allergic diseases in human beings and animals. It aims to re-direct the immune system into a... (Review)
Review
Allergen immunotherapy is currently the only causal treatment for allergic diseases in human beings and animals. It aims to re-direct the immune system into a tolerogenic or desensitized state. Requirements include clinical efficacy, safety, and schedules optimizing patient or owner compliance. To achieve these goals, specific allergens can be formulated with adjuvants that prolong tissue deposition and support uptake by antigen presenting cells, and/or provide a beneficial immunomodulatory action. Here, we depict adjuvant formulations being investigated for human and veterinary allergen immunotherapy.
Topics: Adjuvants, Immunologic; Allergens; Animals; Desensitization, Immunologic; Drug Compounding; Humans; Hypersensitivity; Immune Tolerance; Veterinary Drugs
PubMed: 32849594
DOI: 10.3389/fimmu.2020.01697 -
Structure (London, England : 1993) Jul 2018To what extent do structural and biophysical features of food allergen proteins distinguish them from other proteins in our diet? Invertebrate tropomyosins (Tpms) as a... (Comparative Study)
Comparative Study
To what extent do structural and biophysical features of food allergen proteins distinguish them from other proteins in our diet? Invertebrate tropomyosins (Tpms) as a class are considered "pan-allergens," inducing food allergy to shellfish and respiratory allergy to dust mites. Vertebrate Tpms are not known to elicit allergy or cross-reactivity, despite their high structural similarity and sequence identity to invertebrate homologs. We expect allergens are sufficiently stable against gastrointestinal proteases to survive for immune sensitization in the intestines, and that proteolytic stability will correlate with thermodynamic stability. Thermal denaturation of shrimp Tpm shows that it is more stable than non-allergen vertebrate Tpm. Shrimp Tpm is also more resistant to digestion. Molecular dynamics uncover local dynamics that select epitopes and global differences in flexibility between shrimp and pig Tpm that discriminate allergens from non-allergens. Molecular determinants of allergenicity depend not only on sequence but on contributions of protein structure and dynamics.
Topics: Allergens; Animals; Arthropod Proteins; Cross Reactions; Epitopes; Humans; Models, Molecular; Molecular Dynamics Simulation; Penaeidae; Protein Denaturation; Sequence Homology, Amino Acid; Shellfish Hypersensitivity; Swine; Tropomyosin
PubMed: 29887498
DOI: 10.1016/j.str.2018.05.002 -
Food Chemistry Dec 2022Regulations of the EU obliges the indication of the presence of allergens on food labels. This work reports the development of an electrochemical immunosensor to...
Regulations of the EU obliges the indication of the presence of allergens on food labels. This work reports the development of an electrochemical immunosensor to determine tropomyosin (TPM) - a major shellfish allergen - prevailing in the muscles of crustacean species. Two linear ranges between the signal and TPM concentration were obtained: between 2.5 and 20 ng mL and between 30 and 200 ng mL, with a lowest limit of detection of 0.47 ng mL. The selectivity of the optimized immunoassay, tested with other food allergens (e.g., Cyp c 1, a fish allergen), assures the effective detection of TPM, enabling successful control of foodstuff labelling. Several (12) foods, containing high and low TPM concentrations and TPM-free samples, were analysed using the sensor. A conventional ELISA kit and recovery assays were used to evaluate the accuracy of the results.
Topics: Allergens; Animals; Biosensing Techniques; Food Analysis; Food Hypersensitivity; Immunoassay; Tropomyosin
PubMed: 35839727
DOI: 10.1016/j.foodchem.2022.133659 -
Allergology International : Official... Oct 2016Due to the high prevalence of food allergic diseases globally there are increasing demands in clinical practice for managing IgE-mediated conditions. During the last... (Review)
Review
Due to the high prevalence of food allergic diseases globally there are increasing demands in clinical practice for managing IgE-mediated conditions. During the last decade, component resolved diagnostics has been introduced into the field of clinical allergology, providing information that cannot be obtained from extract-based tests. Component resolved data facilitate more precise diagnosis of allergic diseases and identify sensitizations attributable to cross-reactivity. Furthermore it assists risk assessment in clinical practice as sensitization to some allergenic molecules is related to persistence of clinical symptoms and systemic rather than local reactions. The information may also aid the clinician in prescription of oral immunotherapy (OIT) in patients with severe symptoms, and in giving advice on food allergen avoidance or on the need to perform food challenges. The use of allergen components is rapidly evolving and increases our possibility to treat food allergic patients with a more individual approach. Using molecular allergology, we can already now better diagnose, prognose and grade the food allergy. In summary, daily routine molecular allergy diagnostics offers a number of benefits that give us a higher diagnostic precision and allow for better management of the patient.
Topics: Allergens; Animals; Cross Reactions; Desensitization, Immunologic; Food; Food Hypersensitivity; Humans; Immune Tolerance; Immunoglobulin E
PubMed: 27543004
DOI: 10.1016/j.alit.2016.07.002 -
Food Chemistry Jul 2022This study improves LC-MS-based trace level peanut allergen quantification in processed food by refining method robustness, total analysis time and method sensitivity....
This study improves LC-MS-based trace level peanut allergen quantification in processed food by refining method robustness, total analysis time and method sensitivity. Extraction buffer (six compared) and peptide choice were optimised and found to profoundly affect method robustness. A rapid extraction and in-solution digestion method was developed omitting subsequent reduction, alkylation and sample clean-up steps effectively reducing total analysis time from the previously reported ∼5.5-20 h to ∼2.5 h. For the three best performing peptides, accurate quantification (CVs < 15%) with matrix-matched calibration curves (R = 0.99-0.97) was achieved for peanut muffin and ice-cream with excellent linearity (0.25-1000 mg kg). The best performing peptide enabled excellent recovery rates in ice-cream (106.0 ± 15.1%) and peanut muffin (72.7 ± 13.4%). Sensitivity (LOD = 0.25-0.5 mg kg; LOQ = 0.5-1.0 mg kg) was 2- to 20-fold improved compared to previous methods depending on the peptide. These methodological improvements contribute to robust peanut detection in food and can be translated to additional food-borne allergens.
Topics: Allergens; Arachis; Food Analysis; Food Hypersensitivity; Peptides; Plant Proteins; Proteomics
PubMed: 35413757
DOI: 10.1016/j.foodchem.2022.132592 -
Iranian Journal of Allergy, Asthma, and... Oct 2022Allergen-specific immunotherapy (AIT) involves administering allergen extracts. It is used to desensitize allergic patients. Herbal allergen extracts that are optimum in... (Review)
Review
Allergen-specific immunotherapy (AIT) involves administering allergen extracts. It is used to desensitize allergic patients. Herbal allergen extracts that are optimum in efficacy and fewest in side effects are still challenging to produce. To overcome these limitations, oral immunotherapy, epicutaneous immunotherapy, intralymphatic immunotherapy, and artificial recombinant allergen preparations have been evaluated. Recombinant allergens have become more popular with the development of molecular diagnostics and therapeutics. Besides food and drug allergens, pollen, fungal spores, and other allergens have been studied. Based on related clinical studies, this comprehensive overview will present the latest perspectives on AIT methods and available allergenic products, as well as discuss the challenges and opportunities for treating allergic disorders.
Topics: Humans; Allergens; Desensitization, Immunologic; Hypersensitivity; Pollen; Plant Extracts
PubMed: 36341559
DOI: 10.18502/ijaai.v21i5.11038 -
Toxins Jul 2015Along with food and drug allergic reactions, a Hymenoptera insect Sting (Apoidea, Vespidae, Formicidae) is one of the most common causes of anaphylaxis worldwide.... (Review)
Review
Along with food and drug allergic reactions, a Hymenoptera insect Sting (Apoidea, Vespidae, Formicidae) is one of the most common causes of anaphylaxis worldwide. Diagnoses of Hymenoptera venom allergy (HVA) and specific immunotherapy (SIT) have been based on the use of crude venom extracts. However, the incidence of cross-reactivity and low levels of sensibility during diagnosis, as well as the occurrence of nonspecific sensitization and undesired side effects during SIT, encourage the search for novel allergenic materials. Recombinant allergens are an interesting approach to improve allergy diagnosis and SIT because they circumvent major problems associated with the use of crude venom. Production of recombinant allergens depends on the profound molecular characterization of the natural counterpart by combining some "omics" approaches with high-throughput screening techniques and the selection of an appropriate system for heterologous expression. To date, several clinically relevant allergens and novel venom toxins have been identified, cloned and characterized, enabling a better understanding of the whole allergenic and envenoming processes. Here, we review recent findings on identification, molecular characterization and recombinant expression of Hymenoptera venom allergens and on the evaluation of these heterologous proteins as valuable tools for tackling remaining pitfalls on HVA diagnosis and immunotherapy.
Topics: Allergens; Animals; Arthropod Venoms; Cloning, Molecular; Desensitization, Immunologic; Humans; Hymenoptera; Hypersensitivity; Proteome; Recombinant Proteins; Transcriptome
PubMed: 26184309
DOI: 10.3390/toxins7072551 -
European Respiratory Review : An... Apr 2024Common airborne allergens (pollen, animal dander and those from fungi and insects) are the main triggers of type I allergic disorder in the respiratory system and are... (Review)
Review
Common airborne allergens (pollen, animal dander and those from fungi and insects) are the main triggers of type I allergic disorder in the respiratory system and are associated with allergic rhinitis, allergic asthma, as well as immunoglobulin E (IgE)-mediated allergic bronchopulmonary aspergillosis. These allergens promote IgE crosslinking, vasodilation, infiltration of inflammatory cells, mucosal barrier dysfunction, extracellular matrix deposition and smooth muscle spasm, which collectively cause remodelling of the airways. Fungus and insect (house dust mite and cockroaches) indoor allergens are particularly rich in proteases. Indeed, more than 40 different types of aeroallergen proteases, which have both IgE-neutralising and tissue-destructive activities, have been documented in the Allergen Nomenclature database. Of all the inhaled protease allergens, 85% are classed as serine protease activities and include trypsin-like, chymotrypsin-like and collagenolytic serine proteases. In this article, we review and compare the allergenicity and proteolytic effect of allergen serine proteases as listed in the Allergen Nomenclature and MEROPS databases and highlight their contribution to allergic sensitisation, disruption of the epithelial barrier and activation of innate immunity in allergic airways disease. The utility of small-molecule inhibitors of allergen serine proteases as a potential treatment strategy for allergic airways disease will also be discussed.
Topics: Humans; Allergens; Serine Proteases; Animals; Immunity, Innate; Air Pollution, Indoor; Serine Proteinase Inhibitors; Inhalation Exposure; Respiratory Hypersensitivity
PubMed: 38657996
DOI: 10.1183/16000617.0126-2023