Vigilancia epidemiológica en los últimos 4 años del Registro Español de Investigación en Dermatitis de Contacto y Alergia Cutánea: situación actual y tendencias / Four-year Epidemiological Surveillance of the Spanish Registry of Research in Contact Dermatitis and Cutaneous Allergy: Current Situation and Trends

Antecedentes: El Registro Español de Investigación en Dermatitis de Contacto y Alergia Cutánea tiene entre sus objetivos la vigilancia epidemiológica de la dermatitis de contacto. Para ello es importante conocer si se producen alteraciones en el tiempo de las prevalencias de las positividades a los distintos alérgenos. Objetivos: Describir las variaciones en las tendencias temporales en positividades a alérgenos en la serie estándar del GEIDAC en el periodo comprendido entre 2018 y el 31 de diciembre de 2022. Métodos: Estudio observacional multicéntrico de pacientes estudiados consecutivamente mediante pruebas epicutáneas dentro del estudio de un posible eczema alérgico de contacto recogidos de forma prospectiva en el seno del Registro Español de Investigación en Dermatitis de Contacto y Alergia Cutánea. Se analizaron los datos mediante 2 pruebas estadísticas: una de homogeneidad (para ver si hay cambios en los diferentes años) y otra de tendencia (para ver si los cambios siguen una tendencia lineal). Resultados: Se incluyeron un total de 11.327 pacientes en el periodo de estudio. Los alérgenos en los que de forma global se detectó una sensibilización mayor fueron sulfato de níquel, metilisotiazolinona, cloruro de cobalto, metilcloroisotiazolinona/metilisotiazolinona y mezcla de fragancias i. Se detectó una disminución estadísticamente significativa en el porcentaje de positividades de metilisotiazolinona a lo largo de años de estudio con una tendencia ordenada. Conclusiones: Si bien se pueden apreciar diferentes cambios en las tendencias a sensibilizaciones a varios de los alérgenos de la batería estándar, se observa que persiste una alta sensibilización al níquel, a la metilcloroisotiazolinona/metilisotiazolinona y a la mezcla de fragancias i. Solo se aprecia una tendencia a disminuir de forma significativa en el caso de la metilisotiazolinona.(AU)

Background: The epidemiological surveillance of contact dermatitis is one of the objectives of the Spanish Registry of Research in Contact Dermatitis and Cutaneous Allergy. Knowing whether the prevalence of positive tests to the different allergens changes over time is important for this monitoring process. Objectives: To describe the various temporary trends in allergen positivity in the GEIDAC standard series from 2018 through December 31, 2022. Methods: This was a multicenter, observational trial of consecutive patients analyzed via patch tests as part of the study of possible allergic contact dermatitises collected prospectively within the Spanish Registry of Research in Contact Dermatitis and Cutaneous Allergy. The data was analyzed using 2 statistical tests: one homogeneity test (to describe the changes seen over time) and one trend test (to see whether the changes described followed a linear trend). Results: A total of 11327 patients were included in the study. Overall, the allergens associated with a highest sensitization were nickel sulfate, methylisothiazolinone, cobalt chloride, methylchloroisothiazolinone/methylisothiazolinone, and fragrance mix i. A statistically significant decrease was found in the percentage of methylisothiazolinone positive tests across the study years with an orderly trend. Conclusions: Although various changes were seen in the sensitizations trends to several allergens of the standard testing, it became obvious that a high sensitization to nickel, methylchloroisothiazolinone/methylisothiazolinone and fragrances mix i remained. Only a significant downward trend was seen for methylisothiazolinone.(AU)

[Translated article] Four-year Epidemiological Surveillance of the Spanish Registry of Research in Contact Dermatitis and Cutaneous Allergy: Current Situation and Trends / Vigilancia epidemiológica en los últimos 4 años del Registro Español de Investigación en Dermatitis de Contacto y Alergia Cutánea: situación actual y tendencias

Antecedentes: El Registro Español de Investigación en Dermatitis de Contacto y Alergia Cutánea tiene entre sus objetivos la vigilancia epidemiológica de la dermatitis de contacto. Para ello es importante conocer si se producen alteraciones en el tiempo de las prevalencias de las positividades a los distintos alérgenos. Objetivos: Describir las variaciones en las tendencias temporales en positividades a alérgenos en la serie estándar del GEIDAC en el periodo comprendido entre 2018 y el 31 de diciembre de 2022. Métodos: Estudio observacional multicéntrico de pacientes estudiados consecutivamente mediante pruebas epicutáneas dentro del estudio de un posible eczema alérgico de contacto recogidos de forma prospectiva en el seno del Registro Español de Investigación en Dermatitis de Contacto y Alergia Cutánea. Se analizaron los datos mediante 2 pruebas estadísticas: una de homogeneidad (para ver si hay cambios en los diferentes años) y otra de tendencia (para ver si los cambios siguen una tendencia lineal). Resultados: Se incluyeron un total de 11.327 pacientes en el periodo de estudio. Los alérgenos en los que de forma global se detectó una sensibilización mayor fueron sulfato de níquel, metilisotiazolinona, cloruro de cobalto, metilcloroisotiazolinona/metilisotiazolinona y mezcla de fragancias i. Se detectó una disminución estadísticamente significativa en el porcentaje de positividades de metilisotiazolinona a lo largo de años de estudio con una tendencia ordenada. Conclusiones: Si bien se pueden apreciar diferentes cambios en las tendencias a sensibilizaciones a varios de los alérgenos de la batería estándar, se observa que persiste una alta sensibilización al níquel, a la metilcloroisotiazolinona/metilisotiazolinona y a la mezcla de fragancias i. Solo se aprecia una tendencia a disminuir de forma significativa en el caso de la metilisotiazolinona.(AU)

Background: The epidemiological surveillance of contact dermatitis is one of the objectives of the Spanish Registry of Research in Contact Dermatitis and Cutaneous Allergy. Knowing whether the prevalence of positive tests to the different allergens changes over time is important for this monitoring process. Objectives: To describe the various temporary trends in allergen positivity in the GEIDAC standard series from 2018 through December 31, 2022. Methods: This was a multicenter, observational trial of consecutive patients analyzed via patch tests as part of the study of possible allergic contact dermatitises collected prospectively within the Spanish Registry of Research in Contact Dermatitis and Cutaneous Allergy. The data was analyzed using 2 statistical tests: one homogeneity test (to describe the changes seen over time) and one trend test (to see whether the changes described followed a linear trend). Results: A total of 11327 patients were included in the study. Overall, the allergens associated with a highest sensitization were nickel sulfate, methylisothiazolinone, cobalt chloride, methylchloroisothiazolinone/methylisothiazolinone, and fragrance mix i. A statistically significant decrease was found in the percentage of methylisothiazolinone positive tests across the study years with an orderly trend. Conclusions: Although various changes were seen in the sensitizations trends to several allergens of the standard testing, it became obvious that a high sensitization to nickel, methylchloroisothiazolinone/methylisothiazolinone and fragrances mix i remained. Only a significant downward trend was seen for methylisothiazolinone.(AU)

Sensitization with Fungal Protease Allergen Establishes Long-Lived, Allergenic Th Cell Memory in the Lung.

Allergic asthma is a chronic inflammatory disease that affects millions of individuals worldwide. Exposure to allergens produced by a variety of otherwise harmless microbes, including fungi, predisposes individuals to immunopathologic disease upon subsequent encounters with allergen. We developed a mouse model that employs a purified protease produced by Aspergillus (Asp f 13) to investigate the contributions of CD4+ Th cells to recurrent lung inflammation. Notably, memory CD4+ T cells enhanced the eosinophil response of sensitized/rechallenged animals. In addition, memory CD4+ T cells maintained allergenic features, including expression of GATA-binding protein 3 and IL-5. Th2 memory T cells persisted in the peribronchiolar interstitium of the lung and expressed markers of tissue residence, such as CD69, CCR8, and IL-33R. Lastly, we identified a peptide epitope contained within Asp f 13 and generated a peptide-MHC class II tetramer. Using these tools, we further demonstrated the durability and exquisite sensitivity of memory T cells in promoting lung eosinophilia. Our data highlight important features of memory T cells that strengthen the notion that memory T cells are principal drivers of eosinophilic disease in murine models of allergic sensitization and episodic airway inflammation.

Imported allergens in Italy: an emerging issue.

Imported allergens are involved in many allergic reactions, with unexpected and unusual implications. They can be involved in developing asthma, allergic rhinoconjunctivitis, Hymenoptera venom allergies and food allergies. Imported allergens can be implied in respiratory allergies attributable to commercial practices and accidental diffusion through air currents that have introduced non-native species in new geographical contexts. Ambrosia artemisiifolia L., a plant native to North America and currently in the western part of Lombardy, represents an example. Moreover, a variation in the pollen concentration in the Northwest Tuscany area and Trentino Alto-Adige was observed. Cannabis sativa is another imported allergen used frequently by adolescents. Regarding potential imported food allergens, there is no validated list. Imported food allergens derive from ethnic foods, referring to Mexican/Latin American, Chinese/Japanese, Southeast Asian, Arab/Middle Eastern and African cuisine. Four insect flours were recently introduced to the European and Italian markets (Acheta domesticus, Alphitobius diaperinus, Tenebrio molitor and Locusta migratoria). The association between the accidental introduction through commercial traffic, climate change, and the absence of natural enemies in the destination ecosystem is related to the introduction of a specific Hymenoptera, Vespa velutina, in Italy and Europe. External events attributable to human activities, such as climate change and the introduction of non-native plants, foods and Hymenoptera through trade, have contributed to the issue of imported allergens. Making the correct diagnosis and guiding the diagnostic and therapeutic path in this particular context represent the concerns of the pediatric allergist.

Identification, Characterization, Cloning, and Cross-Reactivity of Zan b 2, a Novel Pepper Allergen of 11S Legumin.

Protein from Sichuan peppers can elicit mild to severe allergic reactions. However, little is known about their allergenic proteins. We aimed to isolate, identify, clone, and characterize Sichuan pepper allergens and to determine its allergenicity and cross-reactivities. Sichuan pepper seed proteins were extracted and then analyzed by SDS-PAGE. Western blotting was performed with sera from Sichuan pepper-allergic individuals. Proteins of interest were purified using hydrophobic interaction chromatography and gel filtration and further analyzed by analytical ultracentrifugation, circular dichroism spectroscopy, and mass spectrometry (MS). Their coding region was amplified in the genome. IgE reactivity and cross-reactivity of allergens were evaluated by dot blot, enzyme-linked immunosorbent assay (ELISA), and competitive ELISA. Western blot showed IgE binding to a 55 kDa protein. This protein was homologous to the citrus proteins and has high stability and a sheet structure. Four DNA sequences were cloned. Six patients' sera (60%) showed specific IgE reactivity to this purified 11S protein, which was proved to have cross-reactivation with extracts of cashew nuts, pistachios, and citrus seeds. A novel allergen in Sichuan pepper seeds, Zan b 2, which belongs to the 11S globulin family, was isolated and identified. Its cross-reactivity with cashew nuts, pistachios, and citrus seeds was demonstrated.

Electrochemical bioplatform to manage alpha-gal syndrome by tracking the carbohydrate allergen in meat.

This work presents the first bioplatform described to date for the determination of galactose-α-1,3-galactose (α-Gal), a non-primate mammalian oligosaccharide responsible for almost all cases of red meat allergy. The bioplatform is based on the implementation of an indirect competitive immunoassay and enzymatic labeling with the enzyme horseradish peroxidase (HRP) built on the surface of magnetic microparticles (MBs) and amperometric transduction on screen-printed carbon electrodes (SPCEs) using the H2O2/hydroquinone (HQ) system. The target α-Gal competed with biotinylated α-Gal immobilized on the surface of neutravidin-modified MBs for the limited immunorecognition sites of a detection antibody enzymatically labeled with an HRP-conjugated secondary antibody. The resulting magnetic immunoconjugates were trapped on the surface of the SPCE working electrode and amperometric transduction was performed, providing a cathodic current variation inversely proportional to the concentration of α-Gal in the analyzed sample. The developed biotool was optimized, characterized and applied with satisfactory results to the determination of the target allergen in different samples of raw and processed meats.

Method to develop a regional guide for the allergenic potential of tree pollen.

Allergic rhinitis, caused by airborne pollen, is a common disease with a great impact on the quality of life for patients and high costs for society. Prevention of high pollen concentrations in the air is relevant for creating a safe environment for allergic patients. Due to climate change, the heat in cities during the summer is a recurring problem. The local climate can be improved by using the cooling properties of trees, providing shade and cooling by evapotranspiration. When deciding which tree species will be planted, it is important to take into account the allergenicity of the pollen that the tree produces. Available guides, used all over the world, on the allergenicity of pollen are very divers in content and interpretation and not applicable for the Netherlands. In this study a method is described to develop a guide for the allergenic potential of tree pollen in a region, in this case the Netherlands. For the most common tree species in the Netherlands the scientific knowledge on the allergenicity of the pollen was collected, followed by an inventory on regional pollen abundance. Subsequently, the sensitization pattern in a patient group with possible inhalation allergy was analyzed. Based on these data allergenicity of the tree pollen was classified into five classes. Eight tree species/genera of the 61 most planted tree species in the Netherlands are considered to have a very strong to moderate allergenic potential. We propose to use this methodology to develop regional-specific guides classifying the allergenic potential of tree pollen.

COBRAPed cohort: Do sensitization patterns differentiate children with severe asthma from those with a milder disease?

BACKGROUND: It is unclear whether sensitization patterns differentiate children with severe recurrent wheeze (SRW)/severe asthma (SA) from those with non-severe recurrent wheeze (NSRW)/non-severe asthma (NSA). Our objective was to determine whether sensitization patterns can discriminate between children from the French COBRAPed cohort with NSRW/NSA and those with SRW/SA. METHODS: IgE to 112 components (c-sIgE) (ImmunoCAP® ISAC) were analyzed in 125 preschools (3-6 years) and 170 school-age children (7-12 years). Supervised analyses and clustering methods were applied to identify patterns of sensitization among children with positive c-sIgE. RESULTS: We observed c-sIgE sensitization in 51% of preschool and 75% of school-age children. Sensitization to house dust mite (HDM) components was more frequent among NSRW than SRW (53% vs. 24%, p < .01). Sensitization to non-specific lipid transfer protein (nsLTP) components was more frequent among SA than NSA (16% vs. 4%, p < .01) and associated with an FEV1/FVC < -1.64 z-score. Among sensitized children, seven clusters with varying patterns were identified. The two broader clusters identified in each age group were characterized by "few sensitizations, mainly to HDM." One cluster (n = 4) with "multiple sensitizations, mainly to grass pollen, HDM, PR-10, and nsLTP" was associated with SA in school-age children. CONCLUSIONS: Although children with wheeze/asthma display frequent occurrences and high levels of sensitization, sensitization patterns did not provide strong signals to discriminate children with severe disease from those with milder disease. These results suggest that the severity of wheeze/asthma may depend on both IgE- and non-IgE-mediated mechanisms.

[TWO CASES OF ALLERGIC VULVOVAGINITIS DIAGNOSED BY DIRECT MICROSCOPIC URINE SEDIMENT EXAMINATION].

Cedar pollen is known as a typical allergen that causes various allergic symptoms in the nasal mucosa, conjunctiva, and skin. However, inflammation of the vulvar mucosa due to sensitization to cedar pollen is not well-known. We experienced two cases in which the detection of cedar pollen during microscopic urine sediment examination led to the diagnosis of allergic vulvovaginitis caused by cedar pollen. The cases involved a 4-year-old girl and a 10-year-old girl. In both cases, the patients presented with chief complaints of pruritis in the vulva and insomnia due to frequent urination during the season of cedar pollen dissemination. Both patients were afebrile. No inflammatory skin changes such as erythema, swelling, or non-purulent discharge from mucous membranes of the vulva were observed. Microscopic urine sediment examination revealed large amounts of shed cedar pollen. The patients' conditions improved after treatment with oral antihistamines and instruction to dry their underwear indoors. Follow-up blood tests revealed high levels of specific anti-IgE antibodies to cedar pollen, thus confirming a diagnosis of allergic vulvovaginitis due to cedar pollen. Cedar pollen can cause allergic vulvovaginitis. Microscopic urine sediment examination is useful, and when combined with specific IgE antibody testing, leads to an appropriate diagnosis. This disease should also be considered in patients with complaints of vulvar discomfort during the season of cedar pollen dissemination.

Allergic to bureaucracy? Regulatory allergenicity assessments of novel food: Motivations, challenges, compromises, and possibilities.

New sources of proteins are essential to meet the demands of the growing world population and evolving food trends. Assessing the allergenicity of proteins in novel food (NF) poses a significant food safety regulatory challenge. The Codex Alimentarius Commission presented an allergenicity assessment protocol for genetically modified (GM) foods, which can also be adapted for NF. Since no single laboratory test can adequately predict the allergenic potential of NF, the protocol follows a weight-of-evidence approach, evaluated by experts, as part of a risk management process. Regulatory bodies worldwide have adopted this safety protocol, which, among other things, promotes global harmonization. This review unravels the reliability and various motivations, terms, concepts, and approaches of allergenicity assessments, aiming to enhance understanding among manufacturers and the public. Health Canada, Food Safety Commission JAPAN, and Food Standards Australia New Zealand were surveyed, focusing on the European Food Safety Authority and the US Food Safety Administration for examples of scientific opinions regarding allergenicity assessments for novel and GM foods, from 2019 to 2023. According to our findings, current regulatory allergenicity assessments for NF approval primarily rely on literature reviews. Only a few of the NF assessments proactively presented additional tests. We recommend conducting bioinformatic analyses on NF when a panel of experts deems that there is insufficient prior scientific research.

Coupling of a Major Allergen to the Surface of Immune Cells for Use in Prophylactic Cell Therapy for the Prevention of IgE-Mediated Allergy.

Up to a third of the world's population suffers from allergies, yet the effectiveness of available preventative measures remains, at large, poor. Consequently, the development of successful prophylactic strategies for the induction of tolerance against allergens is crucial. In proof-of-concept studies, our laboratory has previously shown that the transfer of autologous hematopoietic stem cells (HSC) or autologous B cells expressing a major grass pollen allergen, Phl p 5, induces robust tolerance in mice. However, eventual clinical translation would require safe allergen expression without the need for retroviral transduction. Therefore, we aimed to chemically couple Phl p 5 to the surface of leukocytes and tested their ability to induce tolerance. Phl p 5 was coupled by two separate techniques, either by 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) or by linkage via a lipophilic anchor, 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-poly(ethylene glycol)-maleimide (DSPE-PEG-Mal). The effectiveness was assessed in fresh and cultured Phl p 5-coupled cells by flow cytometry, image cytometry, and immunofluorescence microscopy. Chemical coupling of Phl p 5 using EDC was robust but was followed by rapid apoptosis. DSPE-PEG-Mal-mediated linkage was also strong, but antigen levels declined due to antigen internalization. Cells coupled with Phl p 5 by either method were transferred into autologous mice. While administration of EDC-coupled splenocytes together with short course immunosuppression initially reduced Phl p 5-specific antibody levels to a moderate degree, both methods did not induce sustained tolerance towards Phl p 5 upon several subcutaneous immunizations with the allergen. Overall, our results demonstrate the successful chemical linkage of an allergen to leukocytes using two separate techniques, eliminating the risks of genetic modifications. More durable surface expression still needs to be achieved for use in prophylactic cell therapy protocols.

Botanical Impurities in the Supply Chain: A New Allergenic Risk Exacerbated by Geopolitical Challenges.

BACKGROUND: The supply chains of food raw materials have recently been heavily influenced by geopolitical events. Products that came from, or transited through, areas currently in conflict are now preferentially supplied from alternative areas. These changes may entail risks for food safety. METHODS: We review the potential allergenicity of botanical impurities, specifically vegetable contaminants, with particular attention to the contamination of vegetable oils. We delve into the diverse types of botanical impurities, their sources, and the associated allergenic potential. Our analysis encompasses an evaluation of the regulatory framework governing botanical impurities in food labeling. RESULTS: Unintended plant-derived contaminants may manifest in raw materials during various stages of food production, processing, or storage, posing a risk of allergic reactions for individuals with established food allergies. Issues may arise from natural occurrence, cross-contamination in the supply chain, and contamination at during production. The food and food service industries are responsible for providing and preparing foods that are safe for people with food allergies: we address the challenges inherent in risk assessment of botanical impurities. CONCLUSIONS: The presence of botanical impurities emerges as a significant risk factor for food allergies in the 2020s. We advocate for regulatory authorities to fortify labeling requirements and develop robust risk assessment tools. These measures are necessary to enhance consumer awareness regarding the potential risks posed by these contaminants.

Intervention Efficacy of Slightly Processed Allergen/Meat in Oral Immunotherapy for Seafood Allergy: A Systematic Review, Meta-Analysis, and Meta-Regression Analysis in Mouse Models and Clinical Patients.

Background: Seafood allergy is a significant global health concern that greatly impacts a patient's quality of life. The intervention efficacy of oral immunotherapy (OIT), an emerging intervention strategy, for seafood allergy remains controversial. This study aimed to perform a systematic review and meta-analysis to evaluate the efficacy of slightly processed allergen/meat from fish and crustacea in OIT, both in mouse models and clinical patients. Methods: A comprehensive literature search was performed in four mainstream databases and the EBSCOhost database to identify all relevant case-control and cohort studies. The aim was to elucidate the intervention efficacy, encompassing various processing methods and assessing the efficacy of multiple major allergens in OIT. Results: The meta-analysis included five case-control studies on crustacean allergens in mouse models and 11 cohort studies on meat from fish and crustacea in clinical patients for final quantitative assessments. In mouse models, crustacean allergen substantially decreased the anaphylactic score after OIT treatment (mean difference (MD) = -1.30, p < 0.01). Subgroup analyses with low-level heterogeneities provided more reliable results for crab species (MD = -0.63, p < 0.01, I2 = 0), arginine kinase allergen (MD = -0.83, p < 0.01, I2 = 0), and Maillard reaction processing method (MD = -0.65, p < 0.01, I2 = 29%), respectively. In clinical patients, the main meta-analysis showed that the slightly processed meat significantly increased the incidence rate of oral tolerance (OT, incidence rate ratio (IRR) = 2.90, p < 0.01). Subgroup analyses for fish meat (IRR = 2.79, p < 0.01) and a simple cooking treatment (IRR = 2.36, p = 0.01) also demonstrated a substantial increase in the incidence rate of OT. Sensitivity and meta-regression analyses successfully identified specific studies contributing to heterogeneity in mouse models and clinical patients, although these studies did not impact the overall significant pooled effects. Conclusions: This meta-analysis provides preliminary evidence for the high intervention efficacy of slightly processed allergen/meat from fish and crustacea in OIT, both in mouse models and clinical patients. The Maillard reaction and cooking processing methods may emerge as potentially effective approaches to treating allergen/meat in OIT for clinical patients, offering a promising and specific treatment strategy for seafood allergy. However, these findings should be interpreted cautiously, and further supporting evidence is necessary.

Relationship between dust allergen sensitization and cardiac autonomic function in patients with chronic obstructive pulmonary disease.

OBJECTIVE: Cardiac autonomic function predicts cardiovascular disease risk. The aim of this study was to investigate the relationship between sensitization to dust allergens and cardiac autonomic dysfunction in patients with chronic obstructive pulmonary disease (COPD), and to provide new ideas for the prevention of cardiovascular complications in these patients. METHODS: Immunoassays for sensitization to cats/dogs, cockroaches and dust mites were performed in 840 patients with COPD. Indicators of heart rate variability in these patients were used to assess cardiac autonomic function, including standard deviation of normal-to-normal intervals (SDNN), root-mean square of successive differences between normal-to-normal intervals (RMSSD), low-frequency power (LF), high-frequency power (HF), and LF/HF ratios, which were obtained based on ambulatory electrocardiographic monitoring data. The relationship between sensitization to these dust allergens and heart rate variability was explored using multivariate logistic regression. FINDINGS: The multivariate analyses showed that sensitization to total allergens was associated with reduced levels of SDNN, RMSSD, LF and HF and with increased levels of the LF/HF ratio in the patients with COPD (p < .05). CONCLUSION: Dust allergen sensitization may be associated with cardiac autonomic dysfunction in patients with COPD. Whether desensitization can prevent cardiovascular complications in these patients should be further explored.

Fungal Spore Richness and Abundance of Allergenic Taxa: Comparing a Portable Impactor and Passive Trap Indoors and Outdoors in an Urban Setting.

Fungal spores are common airborne allergens, and fungal richness has been implicated in allergic disease. Amplicon sequencing of environmental DNA from air samples is a promising method to estimate fungal spore richness with semi-quantification of hundreds of taxa and can be combined with quantitative PCR to derive abundance estimates. However, it remains unclear how the choice of air sampling method influences these estimates. This study compared active sampling with a portable impactor and passive sampling with a passive trap over different durations to estimate fungal spore richness and the abundance of allergenic taxa. Air sampling was conducted indoors and outdoors at 12 residences, including repeated measurements with a portable impactor and passive traps with 1-day and 7-day durations. ITS2 amplicon sequence data were transformed to spore equivalents estimated by quantitative PCR, repeated active samples were combined, and abundance-based rarefaction was performed to standardize sample coverage for estimation of genus-level richness and spore abundance. Rarefied fungal richness was similar between methods indoors but higher for passive traps with a 7-day duration outdoors. Rarefied abundance of allergenic genera was similar between methods but some genera had lower abundance for passive traps with a 1-day duration, which differed indoors and outdoors indicating stochasticity in the collection of spores on collocated samplers. This study found that similar estimates of fungal spore richness and abundance of allergenic taxa can be obtained using a portable impactor or a passive trap within one day and that increased passive sample duration provides limited additional information.

Reducing the allergenicity of tropomyosin in shrimp by covalent conjugation with quercetin and chlorogenic acid.

The study aimed to assay the allergenicity of shrimp tropomyosin (TM) following covalent conjugation with quercetin (QR) and chlorogenic acid (CA). The structure of the TM-polyphenol covalent conjugates was examined by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), circular dichroism (CD), fluorescence, differential scanning calorimetry (DSC), and Fourier Transform infrared spectroscopy (FTIR). Potential allergenicity was evaluated using in vitro and in vivo methods. The results showed that QR and CA induced structural changes in TM through aggregation. RBL-2H3 cell results showed that TM-QR and TM-CA covalent conjugates reduced the release of ß-hexosaminidase and histamine, respectively. In the mice model, TM-QR and TM-CA covalent conjugates reduced the level of IgE, IgG, IgG1, histamine, and mMCP-1 in sera. Furthermore, the allergenicity was reduced by suppressing Th2-related cytokines (IL-4, IL-5, IL-13) and promoting Th1-related cytokines (IFN-γ). These research findings demonstrate that the covalent binding of TM with QR and CA, modifies the allergenic epitopes of shrimp TM, thereby reducing its potential allergenicity. This approach holds practical applications in the production of low-allergenicity food within the food industry.

New device, 'old' allergens. Allergic contact dermatitis caused by the Dexcom G7 glucose sensor.

BACKGROUND: Allergic contact dermatitis (ACD) has been reported as an adverse effect from the use of several glucose sensors and insulin pumps from different manufacturers. Isobornyl acrylate (IBOA) has been identified as a major culprit sensitizer, but also other acrylates and (modified) colophonium have been reported as causes of ACD. OBJECTIVES: To report the two first cases diagnosed with ACD caused by the Dexcom G7 (DG7) glucose sensor. PATIENTS AND METHODS: Two children with suspected ACD from DG7 were patch tested with our medical device series with an addition of selected test preparations including two variants of modified colophonium - methyl hydrogenated rosinate (MHR) and glyceryl hydrogenated rosinate (GHR). Both patients were also tested with acetone extracts made from different parts of the DG7 sensor. The extracts were analysed by gas chromatography-mass spectrometry (GC-MS). RESULTS: Both patients tested positive to IBOA, hydroabietyl alcohol and GHR. In addition, patient 1 had a positive reaction to MHR and patient 2 had a positive reaction to colophonium. The GC-MS analyses showed the presence of IBOA and colophonium-related substances in the DG7 extracts. CONCLUSIONS: Both patients were diagnosed with contact allergy to well-known medical device-related sensitizers. The presence of IBOA and (modified) colophonium in a newly introduced (on the Swedish market in 2023) glucose sensor is remarkable and indicates an inadequate toxicological assessment of the materials used in the sensor.

Production of a Ric c3 hypo-allergen with no IgE binding or anaphylactogenic activity.

Several studies have been carried out to expand the use of Ricinus communis L. castor bean (Ricinus communis L castor bean.). This oilseed finds appropriate conditions for its development in Brazil, with more than 700 applications. The main allergens of this plant are Ric c1 and Ric c3, that cross-react with various aeroallergens and food allergens such as peanuts, soybeans, corn, and wheat. This study aimed to determine the effect of mutations in Ric c3 amino acid residues known to affect IgE binding and allergy challenges. Based on the Ric c3 structure, B-cell epitopes, and amino acid involved in IgE binding, we produce recombinant mutant protein, mrRic c3, secreted from E. coli. Strategic glutamic acid residues in IgE-biding regions were changed by Leucine. The allergenicity of mrRic c3 was evaluated by determination of IgE, IgG1, and total IgG in immunized Balb/c mice and by degranulation assays of mast cells isolated from Wistar rats. The mrRic c3 presented a percentage of mast cell degranulation close to that seen in the negative control, and the immunization of mice with mrRic c3 presented lower levels of IgE and IgG1 than the group treated with the protein without mutations. The mutant mrRic c3 had an altered structure and reduced ability to stimulate pro-inflammatory responses and bind IgE but retained its ability to induce blocking antibodies. Thus, producing a hypoallergenic mutant allergen (mrRic c3) may be essential in developing new AIT strategies.