-
Journal of Food Protection Jul 2020Preventing the transfer of allergens from one food to another via food contact surfaces in retail food environments is an important aspect of retail food safety....
ABSTRACT
Preventing the transfer of allergens from one food to another via food contact surfaces in retail food environments is an important aspect of retail food safety. Existing recommendations for wiping and cleaning food contact surfaces is mainly focused on preventing microorganisms, such as bacteria and viruses, from contaminating foods. The effectiveness of these wiping and cleaning recommendations for preventing the transfer of food allergens in retail and food service establishments remains unclear. This project investigated (i) allergen removal from surfaces by wiping with paper wipes, terry cloth, and alcohol quaternary ammonium chloride (quat) sanitizing wipes; (ii) cleaning of allergen-contaminated surfaces by using a wash-rinse-sanitize-air dry procedure; and (iii) allergen transfer from contaminated wipes to multiple surfaces. Food contact surfaces (stainless steel, textured plastic, and maple wood) were contaminated with peanut-, milk- and egg-containing foods and subjected to various wiping and cleaning procedures. For transfer experiments, dry paper wipes or wet cloths contaminated with allergenic foods were wiped on four surfaces of the same composition. Allergen-specific lateral flow devices were used to detect the presence of allergen residues on wiped or cleaned surfaces. Although dry wipes and cloths were not effective for removing allergenic foods, terry cloth presoaked in water or sanitizer solution, use of multiple quat wipes, and the wash-rinse-sanitize-air dry procedure were effective in allergen removal from surfaces. Allergens present on dry wipes were transferred to wiped surfaces. In contrast, minimal or no allergen transfer to surfaces was found when allergen-contaminated terry cloth was submerged in sanitizer solution prior to wiping surfaces. The full cleaning method (wash-rinse-sanitize-air dry) and soaking the terry cloth in sanitizer solution prior to wiping were effective at allergen removal and minimizing allergen transfer.
Topics: Allergens; Animals; Egg Hypersensitivity; Food Hypersensitivity; Food Services; Milk
PubMed: 32221544
DOI: 10.4315/JFP-20-025 -
Trends in Biotechnology Jan 2024The global population is growing, rapidly increasing the demand for sustainable, novel, and safe food proteins with minimal risks of food allergy. In vitro testing of... (Review)
Review
The global population is growing, rapidly increasing the demand for sustainable, novel, and safe food proteins with minimal risks of food allergy. In vitro testing of allergy-sensitizing capacity is predominantly based on 2D assays. However, these lack the 3D environment and crosstalk between the gut, skin, and immune cells essential for allergy prediction. Organ-on-a-chip (OoC) technologies are promising to study type 2 immune activation required for sensitization, initiated in the small intestine or skin, in interlinked systems. Increasing the mechanistic understanding and, moreover, finding new strategies to study interorgan communication is of importance to recapitulate food allergen sensitization in vitro. Here, we outline recently developed OoC platforms and discuss the features needed for reliable prediction of sensitizing allergenicity of proteins.
Topics: Humans; Immunoglobulin E; Food Hypersensitivity; Skin; Allergens; Lab-On-A-Chip Devices
PubMed: 37580191
DOI: 10.1016/j.tibtech.2023.07.005 -
The Journal of Allergy and Clinical... May 2023Immunologic mechanism of action of allergoids remains poorly understood. Previous models of allergenicity and immunogenicity have yielded suboptimal knowledge of these...
BACKGROUND
Immunologic mechanism of action of allergoids remains poorly understood. Previous models of allergenicity and immunogenicity have yielded suboptimal knowledge of these immunotherapeutic vaccine products. Novel single-cell RNA sequencing technology offers a bridge to this gap in knowledge.
OBJECTIVE
We sought to identify the underpinning tolerogenic molecular and cellular mechanisms of depigmented-polymerized Phleum pratense (Phl p) extract.
METHODS
The molecular mechanisms underlying native Phl p, depigmented Phl p (DPG-Phl p), and depigmented-polymerized (DPG-POL-Phl p) allergoid were investigated by single-cell RNA sequencing. Allergen-specific T2A, T follicular helper (Tfh), and IL-10 regulatory B cells were quantified by flow cytometry in peripheral blood mononuclear cells from 16 grass pollen-allergic and 8 nonatopic control subjects. The ability of Phl p, DPG-Phl p, and DPG-POL-Phl p to elicit FcεRI- and FcεRII-mediated IgE responses was measured by basophil activation test and IgE-facilitated allergen binding assay.
RESULTS
Analysis revealed that DPG-POL-Phl p downregulated genes associated with T2 signaling, induced functional regulatory T cells exhibiting immunosuppressive roles through CD52 and Siglec-10, modulated genes encoding immunoproteasome that dysregulate the processing and presentation of antigens to T cells and promoted a shift from IgE toward an IgA and IgG responses. In grass pollen-allergic subjects, DPG-POL-Phl p exhibited reduced capacity to elicit proliferation of T2A, IL-4 Tfh and IL-21 Tfh cells while being the most prominent at inducing IL-10CD19CD5 and IL-10CD19CD5CD38CD24 regulatory B-cell subsets compared to Phl p (all P < .05). Furthermore, DPG-POL-Phl p demonstrated a hypoallergenic profile through basophil activation and histamine release compared to Phl p (31.54-fold, P < .001).
CONCLUSIONS
Single-cell RNA sequencing provides an in-depth resolution of the mechanisms underlying the tolerogenic profile of DPG-POL-Phl p.
Topics: Humans; Allergens; Poaceae; Interleukin-10; Leukocytes, Mononuclear; Immunoglobulin E; Pollen; Hypersensitivity; Phleum; Allergoids; Plant Extracts; Sequence Analysis, RNA; Plant Proteins
PubMed: 36649758
DOI: 10.1016/j.jaci.2022.11.030 -
Scientific Reports Jun 2023Mites are mass-cultured to manufacture allergen extracts for allergy diagnostics and therapeutic treatment. This study focused on characterizing the growth, the allergen...
Mites are mass-cultured to manufacture allergen extracts for allergy diagnostics and therapeutic treatment. This study focused on characterizing the growth, the allergen profile, and the microbiome of Dermatophagoides pteronyssinus cultures. Mite population, protein profile, total protein content and major allergen levels (Der p 1, Der p 2, Der p 23) were monitored at different times of three independent cultures. The allergenicity was studied by immunoblot using a pool of sera from allergic patients. Mite microbiome was characterized by sequencing the 16S rRNA gene from 600 adult mites from the last day of the culture. Endotoxin content was also analyzed. The cultures had a fast and unrelenting evolution. Mite density, total protein content, major allergen levels and the allergenicity were increased progressively during the cultures. Regarding the microbiome studies, the results confirm the presence of non-pathogenic bacteria, being firmicutes and actinobacteria the most common bacterial taxa, with a very low content of Gram-negative bacteria and endotoxin content. The allergenicity and levels of the main allergens in the mite cultures are objective methods useful to monitor the mite culture that help to produce standardized allergen extracts. The high presence of Gram-positive bacteria found limits the possibility for vaccine contamination by bacterial endotoxins.
Topics: Adult; Animals; Humans; Allergens; Dermatophagoides pteronyssinus; RNA, Ribosomal, 16S; Hypersensitivity; Endotoxins; Microbiota
PubMed: 37391439
DOI: 10.1038/s41598-023-37045-9 -
Human Vaccines & Immunotherapeutics Oct 2017
Topics: Administration, Oral; Allergens; Desensitization, Immunologic; Humans; Hypersensitivity, Immediate; Injections, Subcutaneous
PubMed: 28933669
DOI: 10.1080/21645515.2017.1374522 -
Immunology and Allergy Clinics of North... Feb 2020Increasing safety while maintaining or even augmenting efficiency are the main goals of research for novel vaccine development and improvement of treatment schemes in... (Review)
Review
Increasing safety while maintaining or even augmenting efficiency are the main goals of research for novel vaccine development and improvement of treatment schemes in allergen immunotherapy (AIT). To increase the efficacy of AIT, allergens have been coupled to innate immunostimulatory substances and new adjuvants have been introduced. Allergens have been modified to increase their uptake and presentation. Hypoallergenic molecules have been developed to improve the safety profile of the vaccines. Administration of recombinant IgG4 antibodies is a new, quick, passive immunization strategy with remarkable efficiency. Results of some current investigations aiming at further improvement of AIT vaccines have been summarized.
Topics: Adjuvants, Immunologic; Allergens; Animals; Desensitization, Immunologic; Humans; Hypersensitivity; Peptide Fragments; Recombinant Proteins; Vaccination; Vaccines
PubMed: 31761116
DOI: 10.1016/j.iac.2019.09.010 -
Allergy Nov 2021The WHO/IUIS Allergen Nomenclature Database (http://allergen.org) provides up-to-date expert-reviewed data on newly discovered allergens and their unambiguous... (Review)
Review
The WHO/IUIS Allergen Nomenclature Database (http://allergen.org) provides up-to-date expert-reviewed data on newly discovered allergens and their unambiguous nomenclature to allergen researchers worldwide. This review discusses the 106 allergens that were accepted by the Allergen Nomenclature Sub-Committee between 01/2019 and 03/2021. Information about protein family membership, patient cohorts, and assays used for allergen characterization is summarized. A first allergenic fungal triosephosphate isomerase, Asp t 36, was discovered in Aspergillus terreus. Plant allergens contained 1 contact, 38 respiratory, and 16 food allergens. Can s 4 from Indian hemp was identified as the first allergenic oxygen-evolving enhancer protein 2 and Cic a 1 from chickpeas as the first allergenic group 4 late embryogenesis abundant protein. Among the animal allergens were 19 respiratory, 28 food, and 3 venom allergens. Important discoveries include Rap v 2, an allergenic paramyosin in molluscs, and Sal s 4 and Pan h 4, allergenic fish tropomyosins. Paramyosins and tropomyosins were previously known mainly as arthropod allergens. Collagens from barramundi, Lat c 6, and salmon, Sal s 6, were the first members from the collagen superfamily added to the database. In summary, the addition of 106 new allergens to the previously listed 930 allergens reflects the continuous linear growth of the allergen database. In addition, 17 newly described allergen sources were included.
Topics: Allergens; Animals; Aspergillus; Food Hypersensitivity; Humans; Tropomyosin; World Health Organization
PubMed: 34310736
DOI: 10.1111/all.15021 -
The Science of the Total Environment Oct 2023The current rise in the prevalence of allergies to aeroallergens is incompletely understood and attributed to interactions with environmental changes and lifestyle... (Review)
Review
The current rise in the prevalence of allergies to aeroallergens is incompletely understood and attributed to interactions with environmental changes and lifestyle changes. Environmental nitrogen pollution might be a potential driver of this increasing prevalence. While the ecological impact of excessive nitrogen pollution has been widely studied and is relatively well understood, its indirect effect on human allergies is not well documented. Nitrogen pollution can affect the environment in various ways, including air, soil, and water. We aim to provide a literature overview of the nitrogen-driven impact on plant communities, plant productivity, and pollen properties and how they lead to changes in allergy burden. We included original articles investigating the associations between nitrogen pollution, pollen, and allergy, published in international peer-reviewed journals between 2001 and 2022. Our scoping review found that the majority of studies focus on atmospheric nitrogen pollution and its impact on pollen and pollen allergens, causing allergy symptoms. These studies often examine the impact of multiple atmospheric pollutants and not just nitrogen, making it difficult to determine the specific impact of nitrogen pollution. There is some evidence that atmospheric nitrogen pollution affects pollen allergy by increasing atmospheric pollen levels, altering pollen structure, altering allergen structure and release, and causing increased allergenic reactivity. Limited research has been conducted on the impact of soil and aqueous nitrogen pollution on pollen allergenic reactivity. Further research is needed to fill the current knowledge gap about the impact of nitrogen pollution on pollen and their related allergic disease burden.
Topics: Humans; Rhinitis, Allergic, Seasonal; Allergens; Pollen; Hypersensitivity; Air Pollution
PubMed: 37321510
DOI: 10.1016/j.scitotenv.2023.164801 -
Journal of Proteomics Oct 2022Exploration of important insect proteins - including allergens - and proteomes can be limited by protein extraction buffer selection and the complexity of the proteome....
Exploration of important insect proteins - including allergens - and proteomes can be limited by protein extraction buffer selection and the complexity of the proteome. Herein, LC-MS/MS-based proteomics experiments were used to assess the protein extraction efficiencies for a suite of extraction buffers and the effect of ingredient processing on proteome and allergen detection. Discovery proteomics revealed that SDS-based buffer yields the maximum number of protein groups from three types of BSF samples. Bioinformatic analysis revealed that buffer composition and ingredient processing could influence allergen detection. Upon applying multi-level filtering criteria, 33 putative allergens were detected by comparing the detected BSF proteins to sequences from public allergen protein databases. A targeted LC-MRM-MS assay was developed for the pan-allergen tropomyosin and used to assess the influence of buffer composition and ingredient processing using peptide abundance measurements. SIGNIFICANCE: We demonstrated that the selection of protein extraction buffer and the processing method could influence protein yield and cross-reactive allergen detection from processed and un-processed black soldier fly (BSF) samples. In total, 33 putative allergens were detected by comparing the detected BSF proteins to sequences from public allergen protein databases. An LC-MRM-MS assay was developed for tropomyosin, indicating the importance of buffer selection and processing conditions to reduce BSF samples' allergenicity.
Topics: Allergens; Animals; Chromatography, Liquid; Diptera; Insect Proteins; Larva; Peptides; Proteome; Tandem Mass Spectrometry; Tropomyosin
PubMed: 36096435
DOI: 10.1016/j.jprot.2022.104724 -
Frontiers in Immunology 2024Type I hypersensitivity, or so-called type I allergy, is caused by Th2-mediated immune responses directed against otherwise harmless environmental antigens. Currently,... (Review)
Review
Type I hypersensitivity, or so-called type I allergy, is caused by Th2-mediated immune responses directed against otherwise harmless environmental antigens. Currently, allergen-specific immunotherapy (AIT) is the only disease-modifying treatment with the potential to re-establish clinical tolerance towards the corresponding allergen(s). However, conventional AIT has certain drawbacks, including long treatment durations, the risk of inducing allergic side effects, and the fact that allergens by themselves have a rather low immunogenicity. To improve AIT, adjuvants can be a powerful tool not only to increase the immunogenicity of co-applied allergens but also to induce the desired immune activation, such as promoting allergen-specific Th1- or regulatory responses. This review summarizes the knowledge on adjuvants currently approved for use in human AIT: aluminum hydroxide, calcium phosphate, microcrystalline tyrosine, and MPLA, as well as novel adjuvants that have been studied in recent years: oil-in-water emulsions, virus-like particles, viral components, carbohydrate-based adjuvants (QS-21, glucans, and mannan) and TLR-ligands (flagellin and CpG-ODN). The investigated adjuvants show distinct properties, such as prolonging allergen release at the injection site, inducing allergen-specific IgG production while also reducing IgE levels, as well as promoting differentiation and activation of different immune cells. In the future, better understanding of the immunological mechanisms underlying the effects of these adjuvants in clinical settings may help us to improve AIT.
Topics: Humans; Desensitization, Immunologic; Hypersensitivity; Adjuvants, Immunologic; Allergens; Aluminum Hydroxide; Adjuvants, Pharmaceutic
PubMed: 38464539
DOI: 10.3389/fimmu.2024.1348305