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Biological & Pharmaceutical Bulletin Oct 2020Japanese allergic subjects are commonly sensitized to both house dust mite (HDM) and Japanese cedar pollen (JCP) and combined treatment with sublingual immunotherapy...
Japanese allergic subjects are commonly sensitized to both house dust mite (HDM) and Japanese cedar pollen (JCP) and combined treatment with sublingual immunotherapy (SLIT) tablets is desirable. However, mixing extracts of two non-homologous allergens may compromise allergen stability and affect the clinical outcome. Therefore, we investigated the stability of major allergens and total allergenic reactivity of HDM and JCP SLIT-tablets following dissolution in human saliva or artificial gastric juice. Two fast-dissolving freeze-dried SLIT-tablets were completely dissolved and incubated at 37 °C. Major allergen concentrations and total allergenic reactivity were measured. After mixing and co-incubation of HDM and JCP SLIT tablets in human saliva for 10 min at 37°C, there were no statistically significant changes in major allergen concentrations. In addition, no loss of allergenic reactivity of the mixed two SLIT-tablet solutions was seen. In contrast, complete loss of allergenic reactivity and detectable major allergen concentrations occurred when the two SLIT-tablets were dissolved and incubated in artificial gastric juice. These results demonstrate that HDM or JCP major allergens and the total allergenic reactivity of both SLIT-tablets measured here remain intact after dissolution and co-incubation in human saliva, supporting the possibility of a dual HDM and JCP SLIT-tablet administration regimen if clinically indicated. The complete loss of allergenic reactivity after incubation in artificial gastric juice can furthermore be taken to indicate that the immunological activity of the allergen extracts contained in the two SLIT-tablets is likely to be lost or severely compromised upon swallowing.
Topics: Administration, Sublingual; Allergens; Antigens, Dermatophagoides; Cryptomeria; Drug Compounding; Drug Liberation; Drug Stability; Humans; Japan; Mouth Mucosa; Oral Mucosal Absorption; Pollen; Rhinitis, Allergic; Saliva; Sublingual Immunotherapy; Tablets; Treatment Outcome
PubMed: 32759600
DOI: 10.1248/bpb.b20-00330 -
Allergy Nov 2015Allergen immunotherapy is a treatment modality which can be applied using different vaccines. The aim of this study was to quantify and compare the allergen content of... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Allergen immunotherapy is a treatment modality which can be applied using different vaccines. The aim of this study was to quantify and compare the allergen content of different house dust mites (HDM)' sublingual treatments and to review the evidence on their efficacy.
METHODS
Five sublingual allergen immunotherapy (SLIT) products were ordered and purchased at an ordinary pharmacy and masked for blinding before the study was started. Detection of Dermatophagoides pteronyssinus and Dermatophagoides farinae allergens Der p 1, Der f 1, Der p 2 and Der f 2 was carried out by immunoblotting and fluorescent multiplex. A literature search for meta-analyses and systematic reviews that included SLIT-HDM products was performed.
RESULTS
Der p 1 concentrations ranged from 0.6 to 14.5 μg/ml; similar figures were found for Der f 1 that ranged from 0.2 to 12.4 μg/ml. Der p 2+ Der f 2 ranged from 0.2 to 1.5 μg/ml. Data on efficacy are scarce for most of the five products.
CONCLUSIONS
Substantial variations regarding allergen content were found among these five SLIT-HDM products. Therefore, it can be necessary to guarantee the quality of the SLIT-HDM products and to demonstrate their effectiveness before they are marketed. It seems necessary, for the moment, to take into account these characteristics of the products before prescribing.
Topics: Allergens; Animals; Antigens, Dermatophagoides; Humans; Hypersensitivity; Pyroglyphidae; Sublingual Immunotherapy; Treatment Outcome; Vaccines
PubMed: 26185961
DOI: 10.1111/all.12694 -
Journal of Proteomics Jun 2016Allergen levels in fresh and processed foods can vary dynamically. As different sources of foods can cause different types of allergic reactions, the food industry and... (Review)
Review
UNLABELLED
Allergen levels in fresh and processed foods can vary dynamically. As different sources of foods can cause different types of allergic reactions, the food industry and regulatory bodies urgently require reliable detection and absolute quantitation methods for allergen detection in complex food products to effectively safeguard the food-allergic population. Recent advances of targeted proteomic technologies namely multiple-reaction monitoring (MRM) mass spectrometry (MS) coupled with isotope-labeled internal standard, also known as AQUA peptides offers absolute quantitation of food allergens even at 10ppb level in a multiplex fashion. However, development of successful AQUA-MRM assay relies on a number of pre and post MS criteria. In this review, we briefly describe how allergen levels could potentially change in plant and animal based foods, necessitating the development of a high throughput multiplexed allergen quantification methodology for successful AQUA-MRM assay. We also propose some future strategies that could provide better management of food allergy.
BIOLOGICAL SIGNIFICANCE
Given the rapid increases of food allergenicity, it has become imperative to know absolute allergen levels in foods. This essential information could be the most effective means of protecting humans suffering from allergies. In this review, we emphasize the significance of the absolute quantitation of food allergens using AQUA-MRM approach and discuss the likely critical steps for successful assay development.
Topics: Allergens; Food Hypersensitivity; Humans; Isotope Labeling; Mass Spectrometry; Proteomics
PubMed: 27113134
DOI: 10.1016/j.jprot.2016.04.018 -
Biosensors Aug 2022The presence of hidden allergens in food products, often due to unintended contamination along the food supply chain (production, transformation, processing, and... (Review)
Review
The presence of hidden allergens in food products, often due to unintended contamination along the food supply chain (production, transformation, processing, and transport), has raised the urgent need for rapid and reliable analytical methods for detecting trace levels of such species in food products. Indeed, food allergens represent a high-risk factor for allergic subjects due to potentially life-threatening adverse reactions. Portable biosensors based on immunoassays have already been developed as rapid, sensitive, selective, and low-cost analytical platforms that can replace analyses with traditional bench-top instrumentation. Recently, aptamers have attracted great interest as alternative biorecognition molecules for bioassays, since they can bind a variety of targets with high specificity and selectivity, and they enable the development of assays exploiting a variety of transduction and detection technologies. In particular, aptasensors based on luminescence detection have been proposed, taking advantage of the development of ultrasensitive tracers and enhancers. This review aims to summarize and discuss recent efforts in the field of food allergen analysis using aptamer-based bioassays with luminescence detection.
Topics: Allergens; Aptamers, Nucleotide; Biological Assay; Biosensing Techniques; Food Hypersensitivity; Humans; Luminescent Measurements
PubMed: 36005040
DOI: 10.3390/bios12080644 -
Indoor Air Jan 2022Exposure to biocontaminants, such as dust mites, animal dander, bacteria, and mold, is associated with a range of health effects. This study identified household...
Exposure to biocontaminants, such as dust mites, animal dander, bacteria, and mold, is associated with a range of health effects. This study identified household characteristics associated with indoor biocontaminant loadings in four Canadian cities. Floor dust was collected in 290 Canadian homes in Edmonton, Halifax, Montreal, and Windsor. The dust samples were analyzed for house dust mite allergens (Der f 1 and Der p 1), cat allergen (Fel d 1), cockroach allergen (Bla g 1), beta-(1,3)-D-glucan, and endotoxin. Household information was obtained through questionnaires and home inspections. We performed univariate and multivariate analyses to identify household determinants of biocontaminant loadings and mold odor presence. We observed large regional variations for all biocontaminants, except for cockroach allergen. The ranges of the contaminants measured in loadings and concentrations were similar to that of previous Canadian studies. Household characteristics including presence of carpeting, low floor cleaning frequency, older home age, presence of pets, and indoor relative humidity above 45% were positively associated with the presence of multiple indoor biocontaminants. High floor cleaning frequency and use of dehumidifiers were negatively associated with the presence of multiple indoor biocontaminants. Mold odor was positively associated with older home age, past water damage, and visible mold growth.
Topics: Air Pollution, Indoor; Allergens; Animals; Antigens, Dermatophagoides; Canada; Cockroaches; Dust; Housing
PubMed: 34561903
DOI: 10.1111/ina.12933 -
Molecular Immunology Aug 2021The Poaceae family is composed of 12,000 plant species. Some of these species produce highly allergenic anemophilous pollen grains (PGs). Phleum pratense pollen grains... (Review)
Review
The Poaceae family is composed of 12,000 plant species. Some of these species produce highly allergenic anemophilous pollen grains (PGs). Phleum pratense pollen grains (PPPGs) emerged as a model for studies related to grass allergy. The biochemical composition of allergenic PGs has not yet been fully described despite potential health effects of PG constituents other than allergenic proteins. This review brings together the information available in literature aiming at creating a comprehensive picture of the current knowledge about the chemical composition of allergenic PGs from timothy grass. PPPGs have an average diameter between 30-35 μm and the mass of a single PG was reported between 11 and 26 ng. The pollen cytoplasm is filled with two types of pollen cytoplasmic granules (PCGs): the starch granules and the polysaccharide particles (p-particles). Starch granules have a size between 0.6-2.5 μm with an average diameter of 1.1 μm (estimated number of 1000 granules per PG) while p-particles have a size ranging around 0.3 to 0.4 μm (estimated number between 61,000-230,000 p-particles per PG). The rupture of PG induces the release of PCGs and the dispersion of allergens in the inhalable fraction of atmospheric aerosol. PPPGs are composed of sporopollenin, sugars, polysaccharides, starch, glycoproteins (including allergens), amino-acids, lipids, flavonoids (including isorhamnetin), various elements (the more abundant being Si, Mg and Ca), phenolic compounds, phytoprostanoids, carotenoids (pigments) metals and adsorbed pollutants. PPPG contains about a hundred different proteins with molecular masses ranging from 10 to 94 kDa, with isoelectric points from 3.5-10.6. Among these proteins, allergens are classified in eleven groups from 1 to 13 with allergens from groups 1 and 5 being the major contributors to Phl p pollen allergy. Major allergen Phl p 5 was quantified in PPPGs by several studies with concentration ranging from 2.7 and 3.5 μg.mg in unpolluted environment. Values for other allergens are scarce in literature; only one quantitative assessment exists for allergen groups Phl p 1, 2 and 4. The extractible lipid fraction of PPPGs is estimated between 1.7-2.2% of the total PG mass. The main chemical families of lipids reported in PPPGs are: alkanes, alkenes, alcohols, saturated and unsaturated fatty acids, di- and tri-hydroxylated fatty acids, aldehydes and sterols. Several lipid compounds with potential adjuvant effects on allergy have been specifically quantified in PPPGs: E2-like prostaglandin (PGE2), B4-like leukotriene (LTB4), unsaturated fatty acids (linoleic and linolenic acids and their hydroxylated derivatives), adenosine, vitamins and phenolic compounds. Some other biochemical characteristics such as NAD(P)H oxidase, protease activity and pollen microbiome were described in the literature. The bioaccessibility in physiological conditions has not been described for most biochemicals transported by allergenic PPPGs. There is also a considerable lack of knowledge about the potential health effects of pollen constituents other than allergens. The variability of pollen composition remains also largely unknown despite its importance for plant reproduction and allergy in an environment characterized by chemical pollution, climate change and loss of biodiversity.
Topics: Allergens; Asthma; Cytoplasmic Granules; Humans; Phleum; Plant Proteins; Pollen; Rhinitis, Allergic, Seasonal
PubMed: 34098345
DOI: 10.1016/j.molimm.2021.05.014 -
Current Allergy and Asthma Reports Aug 2017Allergen extracts are still widely used in allergy diagnosis as they are regarded as sensitive screening tools despite the fact that they may lack some minor allergens.... (Review)
Review
PURPOSE OF REVIEW
Allergen extracts are still widely used in allergy diagnosis as they are regarded as sensitive screening tools despite the fact that they may lack some minor allergens. Another drawback of extracts is their low specificity, which is due to the presence of cross-reactive allergens. Progress in allergen identification has disclosed a number of allergenic molecules of homologous sequence and structure which are present in different animal species. This review summarizes recent advances in mammalian and fish allergen identification and focuses on their clinical relevance.
RECENT FINDINGS
Serum albumins and parvalbumins are well-known animal panallergens. More recently several members of the lipocalin family were found to be cross-reactive between furry animals whereas in fish, additional allergens, enolase, aldolase and collagen, were found to be important and cross-reactive allergens. New epidemiological studies have analysed the prevalence and clinical relevance of mammalian and fish components. Primary sensitization can be distinguished from cross-sensitization by using marker allergens. Although substantial progress has been made in allergen identification, only few markers are commercially available for routine clinical practice.
Topics: Allergens; Animals; Biomarkers; Cross Reactions; Fishes; Food Hypersensitivity; Humans; Immunoglobulin E; Lipocalins; Mammals; Meat; Parvalbumins
PubMed: 28831729
DOI: 10.1007/s11882-017-0732-z -
Revue Medicale de Liege Jun 2024Allergen immunotherapy is still the only curative treatment for respiratory allergies. It is based on repeated administration of allergenic extracts to sensitized... (Review)
Review
Allergen immunotherapy is still the only curative treatment for respiratory allergies. It is based on repeated administration of allergenic extracts to sensitized patients. It can be administered either by subcutaneous or by sublingual route. The purpose of the treatment is to modulate the immune response to a specific allergen and to alter the course of the disease over a long-term period. Numerous studies and meta-analyses have demonstrated its efficacy in terms of symptoms and quality of life improvement as well as reduction of the allergic march. Indication of allergen immunotherapy includes moderate to severe allergic rhinitis and mild to moderate allergic asthma from GINA step 3. Early intervention in sensitized patients is nowadays promoted.
Topics: Humans; Desensitization, Immunologic; Allergens; Asthma; Rhinitis, Allergic
PubMed: 38869131
DOI: No ID Found -
Allergy Mar 2016Owners and their domestic animals via skin shedding and secretions, mutually exchange microbiomes, potential pathogens and innate immune molecules. Among the latter... (Review)
Review
Owners and their domestic animals via skin shedding and secretions, mutually exchange microbiomes, potential pathogens and innate immune molecules. Among the latter especially lipocalins are multifaceted: they may have an immunomodulatory function and, furthermore, they represent one of the most important animal allergen families. The amino acid identities, as well as their structures by superposition modeling were compared among human lipocalins, hLCN1 and hLCN2, and most important animal lipocalin allergens, such as Can f 1, Can f 2 and Can f 4 from dog, Fel d 4 from cats, Bos d 5 from cow's milk, Equ c 1 from horses, and Mus m 1 from mice, all of them representing major allergens. The β-barrel fold with a central molecular pocket is similar among human and animal lipocalins. Thereby, lipocalins are able to transport a variety of biological ligands in their highly conserved calyx-like cavity, among them siderophores with the strongest known capability to complex iron (Fe(3+) ). Levels of human lipocalins are elevated in nonallergic inflammation and cancer, associated with innate immunoregulatory functions that critically depend on ligand load. Accordingly, deficient loading of lipocalin allergens establishes their capacity to induce Th2 hypersensitivity. Our similarity analysis of human and mammalian lipocalins highlights their function in innate immunity and allergy.
Topics: Allergens; Animals; Humans; Hypersensitivity; Immune Tolerance; Immunity, Innate; Immunoglobulin E; Immunomodulation; Lipocalins; Protein Conformation; Structure-Activity Relationship; Th2 Cells
PubMed: 26497994
DOI: 10.1111/all.12797 -
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