Comparison of Intact Allergen Extracts and Allergoids For Subcutaneous Immunotherapy: The Effect of Chemical Modification Differs Both Between Species and Between Individual Allergen Molecules

Background: Allergen products for subcutaneous immunotherapy (SCIT) contain intact allergen extracts or chemically modified allergoids. Chemical modification was introduced to reduce allergenicity while retaining immunogenicity and thereby enable safer and more efficient allergy immunotherapy. Methods: Experimental allergoids were produced from intact allergen extract for birch, grass, and house dust mite (HDM) to evaluate the effects of chemical modification. Preparations were compared with commercial allergoids and analyzed using SDS-PAGE/immunoblotting, IgE-inhibition assays, and crossed immunoelectrophoresis (CIE). Dermatophagoides pteronyssinus (Der p) vaccines were also tested for protease activity and immunizing capacity in a mouse model. Results: The composition of IgE-binding epitopes in allergoids differed from that of intact allergen vaccines. Birch and grass allergoids produced smears of protein aggregates on SDS-PAGE, whereas intact allergen preparations showed distinct protein bands as expected. Der p allergoid vaccines, however, showed a distinct protein band corresponding to major allergen Der p 1 in both SDS-PAGE and CIE analysis, and commercial Der p allergoid vaccines showed Der p 1–related cysteine protease activity. Conclusion: Allergoids and intact allergen preparations differ with respect to the composition of IgE-binding epitopes. However, chemical cross-linking does not affect every allergen molecule to the same degree. Der p 1, for example, remains largely unmodified. Furthermore, the investigational HDM allergoid vaccines showed reduced and delayed immune responses when used for immunization of mice (AU)

Antecedentes: Los productos de alérgenos para inmunoterapia subcutánea (SCIT) contienen extractos de alérgenos intactos o alergoides modificados químicamente. En este trabajo se ha hecho una modificación química para reducir la alergenicidad a la vez que se conservaba la inmunogenicidad, y por lo tanto, permitir una inmunoterapia más segura y eficiente. Métodos: Se produjeron alergoides experimentales a partir de extracto de alérgeno intacto para abedul, hierba y ácaros del polvo doméstico (HDM) y se evaluaron los efectos de la modificación química realizada. Las preparaciones se compararon con alergoides comerciales y se analizaron mediante SDS-PAGE/inmunotransferencia, ensayos de inhibición de IgE e inmunoelectroforesis cruzada (CIE). Las vacunas de Dermatophagoides pteronyssinus (Der p) también se probaron para determinar la actividad de la proteasa y la capacidad de inmunización en un modelo de ratón. Resultados: La composición de los epítopos de unión a IgE en los alergoides difería de las vacunas de alérgenos intactas. Los alergoides de hierba y abedul produjeron manchas de agregados de proteínas en el SDS-PAGE, mientras que las preparaciones de alérgenos intactos mostraron distintas bandas de proteínas como se esperaba. Las vacunas alergoides Der p, sin embargo, mostraron una banda de proteína distinta de la correspondiente al alérgeno principal Der p 1 en los análisis SDS-PAGE y CIE. Las vacunas alergoides comerciales Der p mostraron actividad de cisteína proteasa relacionada con Der p 1.Conclusión: Los alergoides y las preparaciones de alérgenos intactos difieren con respecto a la composición de los epítopos de unión a IgE; sin embargo, el entrecruzamiento químico no afecta a todas las moléculas de alérgenos de un modo similar. Der p 1, por ejemplo, permanece prácticamente sin modificar. Además, las vacunas alergoides de HDM produjeron respuestas inmunitarias reducidas y tardías cuando se usaron para la inmunización de ratones (AU)

Three-year pollen and fungi calendar in a Mediterranean region of the Northeast Greece

Pollen calendars have been proved clinically important in allergic disease management, as differences in airborne allergens exist not only between different countries but also between regions of the same country as well. This study aims to provide new data regarding the atmospheric pollen and fungi content of a Mediterranean region (Western Thrace/North-East Greece) and discuss seasonal trends, differences in pollen grains and fungi spores’ circulation over the years, and correlations with climate parameters.A 7-day continuously running volumetric trap was used to collect circulating pollen grains and fungi spores. Pollen taxa and fungi were characterized by standard protocols and counted as grains /m3 and average total grains and spores. The primary allergenic pollen season was discovered, and their 10-day averages were measured over time. Correlations with temperature, rain, and humidity were assessed by single linear regression analysis.Results Pollen grains from nine pollen families were identified, including five arboreal, two nonarboreal taxa, and spores from two fungi species. The three most prevalent taxa were Oleaceae, Poaceae, Pinaceae, and Cladosporium in the fungi. Peak pollen concentrations were detected during April and May, with daily averages exceeding 170 grains/m3. Poaceae presented the longest pollen season of 342 days and Oleaceae the shortest, extending to only 110 days, during the 3years. Cladosporium was the fungus with the highest spore concentration (180,129.9 spores) compared with Alternaria (28,026.1 spores). Correlations with meteorological parameters showed variable associations among different taxa, with rainfall and relative humidity being the most significant determinants.Conclusion In this study, the pollenic and fungal spectrum of a Mediterranean region and information that can be proved clinically significant for the appropriate diagnostic and therapeutic approach of allergic patients was presented

Association between allergen component sensitisation and clinical allergic disease in children

Background Allergen component sensitisation testing is becoming increasingly important in the diagnosis of peanut allergy. The aim of the present study was to evaluate the relationship between sensitisation and symptoms of allergic disease in children by testing a large panel of inhalants, food allergens, and allergen components.Methods For 287 children visiting our laboratory for allergy testing, symptoms of allergic disease were recorded by standardised validated questionnaires. Specific IgE to 11 whole allergens was assessed by ImmunoCAP, and to 112 allergen components by ISAC ImmunoCAP assay. We used latent class analysis (LCA) to distinguish clinical phenotypes.Results Inhalant and food allergen sensitisation was common, irrespective of the children’s allergic symptom type. Less than 10% of the variance in symptom scores was explained by variations in the number of allergens (components) that the child was sensitised to. In LCA, 135 children (50.2%) had mild allergy, with few symptoms and sensitisation to no or few allergens, 74 children (27.5%) had more symptoms and sensitisation to inhalant allergens (respiratory allergy) and 60 children (22.3%) showed polysensitisation to a median of six allergens and had more severe symptoms of different organ systems. Adding allergen component test results to LCA failed to result in identifiable classes of allergic disease in children.Conclusions In this group of children with allergic symptoms, referred for allergy testing by their physician, broad screening for allergen component sensitisation did not contribute to distinguishing phenotypes of allergic disease (AU)

Association between the type of allergen and T-helper 2 mediated inflammation in allergic reactions: a systematic review and a meta-analysis

Objectives To determine whether the levels of T-helper (TH) 2 cytokines (interleukin (IL)-4 and IL-5) in allergic reactions are allergen dependent and evaluate the impact of various treatment strategies on the levels of these cytokines.Methods The PubMed search engine was used from inception until January 2021. The random-effects residual maximum likelihood model was performed, and effect sizes were estimated using the Hedge’s g statistic. All data analysis was performed using STATA 16.0 (StataCorp LP, TX, USA).Results Fourteen studies reporting on 794 participants were included in this study. House dust mite was associated with eliciting a stronger immune response mediated by both IL-4 and IL-5 when compared to pollen. Whereas a mixture of house dust mite and pollen was associated with IL-4-weighted inflammation. Comparisons of IL-4 and IL-5 levels amongst the allergens showed significant differences. The treatment with anti-corticosteroids or allergen-specific immunotherapy was effective in normalising the TH2 responses and alleviating allergy symptoms (AU).

Influence of the COVID-19 pandemic on the incidence and exacerbation of childhood allergic diseases.

To explore the influence of changes in human lifestyle and the living environment caused by nonpharmaceutical interventions in coronavirus disease 2019 (COVID-19) on allergic diseases, the present study enrolled children who came to the Children's Hospital of Zhejiang University for allergen detection between January 2019 and December 2020. By comparing the positive rates and levels of various allergen-specific immunoglobulin E (IgE) before and during the COVID-19 pandemic, the influence of changes in human lifestyle and the living environment caused by prevention and control measures in COVID-19 on allergic diseases was evaluated. In 2019, 41 648 allergic children went to the hospital, but in 2020, due to the impact of the COVID-19 epidemic, the number decreased to 24 714. In 2020, the number of allergy visits was the lowest in February and gradually increased. There were 45 879 children with total IgE > 17.5 IU/ml in 2 years, accounting for 69.13% of the total samples, of which the proportion was 68.52% (28 536/41 648) in 2019 and 70.17% (17 343/24 714) in 2020. A total of 29 906 children were positive for one or more allergens in 2 years. It accounts for 45.06% of the total number of samples, of which the proportion is 41.53% (17 296/41 648) in 2019 and 51.02% (12 610/24 714) in 2020. Except for cashew nuts, the positive number of other allergens in 2020 was less than in 2019, especially after June and July 2020. Except for Artemisia argyi, the positive rates of other allergens in 2020 were significantly higher than those in 2019 (p < 0.05). Moreover, the changing trend of the positive allergen rate in each month in 2020 was different from that in 2019. In 2020, except for Dermatophagoides farinae, Dermatophagoides pteronyssinus, and Crab, specific IgE levels of other allergens were not greater than those in 2019 (p < 0.05). Thus it can be seen, during the COVID-19 pandemic, nonpharmaceutical interventions played a protective role in reducing children's exposure to allergens and alleviating allergic reactions.

Molecular Allergy Diagnosis in Clinical Practice: Frequently Asked Questions

Considerable progress has been made in the field of molecular biology in recent years, enabling the study of sensitization to the individualcomponents of an allergenic source, a practice that has been termed molecular allergy diagnosis (MD) or component-resolved diagnosis (CRD).The present review provides the clinician with a practical approach to the use of MD by answering questions frequently asked by physicianson how MD can help improve the diagnosis of allergy in daily clinical practice.The article is divided into 3 sections. First, we provide a brief review of the importance for the clinician of knowing the main allergens inthe different allergenic sources, their structure, and their in vitro cross-reactivity before approaching MD (section A). Second, we reviewthe usefulness of MD in clinical practice (section B) and answer frequently asked questions on the subject. Finally, section C addresses theinterpretation of MD and its integration with other tools available for the diagnosis of allergy (AU)

En las últimas décadas ha habido un gran avance en el campo de la biología molecular permitiendo el estudio de la sensibilización acomponentes alergénicos individuales de una fuente alergénica. Dicha práctica se ha denominado Diagnóstico Molecular en alergia (DM)o Diagnóstico por Resolución de Componentes (CRD, según las iniciales en inglés).El propósito de la presente revisión es ofrecer al clínico un enfoque práctico para el uso del DM respondiendo preguntas frecuentes entrelos médicos sobre cómo puede ayudarnos a mejorar el diagnóstico de alergia en nuestra práctica clínica diaria.La revisión se divide en tres secciones. En primer lugar, se realiza una breve revisión sobre la importancia que tiene para el clínico conocerlos principales alérgenos de las diferentes fuentes alergénicas, su estructura y su reactividad cruzada in vitro antes de abordar el DM(apartado A). En segundo lugar, está el núcleo de la revisión sobre la utilidad del DM en la práctica clínica (apartado B) respondiendo alas preguntas frecuentes sobre el tema, y, finalmente, se añade un apartado (C) sobre la interpretación e integración del DM con el restode las herramientas disponibles para el diagnóstico de alergia (AU)

Anaphylaxis: A Decade of a Nationwide Allergy Society Registry

Background: Anaphylaxis is an acute, life-threatening, multiorgan hypersensitivity reaction.Objective: The aim of this study was to identify the causes of anaphylaxis in Portugal in order to improve our knowledge of epidemiology and management.Methods: We implemented a nationwide notification system for anaphylaxis over a 10-year period, with voluntary reporting by allergists. Data on 1783 patients with anaphylaxis were included. Etiopathogenesis, manifestations, and clinical management were characterized in detail for both children and adults.Results: The mean age was 32.7 (20.3) years, and 30% were under 18 years of age; 58% were female. The mean age at the first anaphylaxis episode was 27.5 (20.4) years (ranging from 1 month to 88 years). The main culprits of anaphylaxis were foods (48%), drugs (37%) (main trigger in adults, 48%), and hymenoptera venom (7%). The main culprit foods were shellfish (27%), fresh fruit (17%), cow’s milk (16%), tree nuts (15%), fish (8%), egg (7%), and peanut (7%). The main drugs were nonsteroidal anti-inflammatory drugs (43%), antibiotics (39%), and anesthetic agents (6%). Other causes included exercise (3%), latex (2%), cold-induced anaphylaxis (2%), and idiopathic anaphylaxis (2%). Most patients (80%) were admitted to the emergency department; only 43% received adrenaline. Anaphylaxis recurred in 41% of patients (21% with ≥3 anaphylactic episodes); 7% used an adrenaline autoinjector device.Conclusions: Food is the leading cause of anaphylaxis in Portugal, while drugs were the main elicitors in adults. We emphasize undertreatment with adrenaline and recurrent episodes, highlighting the need to improve diagnostic and therapeutic approaches to anaphylaxis (AU)

Antecedentes: La anafilaxia es una reacción de hipersensibilidad sistémica potencialmente mortal.Objetivo: El objetivo de este estudio fue el identificar las causas de la anafilaxia en Portugal para mejorar el conocimiento de la epidemiologíay del manejo de la enfermedad.Métodos: Durante un período de 10 años, se implementó un sistema nacional de notificación de anafilaxia, por parte de los alergólogos,mediante la emisión de informes voluntarios. Se recogieron datos de 1.783 pacientes con anafilaxia, pediátricos y adultos, relativos a laetiopatogenia, las manifestaciones clínicas y el manejo clínico de la misma.Resultados: La edad media fue de 32,7 ± 20,3 años, siendo el 30% de los pacientes menores de 18 años. El 58% fueron mujeres. Laedad media del primer episodio de anafilaxia fue de 27,5 ± 20,4 años (desde 1 mes hasta 88 años). Los principales agentes responsablesde anafilaxia fueron los alimentos (48%), los medicamentos (37%), que fue el principal desencadenante en los pacientes adultos, y losvenenos de himenópteros (7%). Los principales alimentos responsables fueron: mariscos (27%), frutas frescas (17%), leche de vaca (16%),nueces (15%), pescado (8%), huevo (7%) y cacahuete (7%). Los principales fármacos, fueron los antiinflamatorios no esteroideos (43%),antibióticos (39%) y anestésicos (6%). Entre otras causas implicadas se incluyó: ejercicio físico (3%), látex (2%), frío (2%) e idiopática (2%). La mayoría de los pacientes fueron atendidos en el servicio de urgencias (80%), y solo el 43% recibió tratamiento con adrenalina.La recurrencia de la anafilaxia ocurrió en el 41% de los pacientes (21% con ≥3 episodios anafilácticos). El 7% utilizó un dispositivoautoinyector de adrenalina.Conclusiones: Los alimentos son la principal causa de anafilaxia en Portugal y en el subgrupo de pacientes adultos, lo son los medicamentos

Alérgenos candidatos para ser incluidos en la serie estándar española a partir de los datos del Registro Español de Dermatitis de Contacto / Candidate Allergens for Inclusion in the Spanish Standard Series Based on Data from the Spanish Contact Dermatitis Registry

Antecedentes y objetivo La actualización de las series estándar de pruebas epicutáneas debe basarse en datos objetivos de frecuencia de sensibilización de los alérgenos que componen cada batería. La última renovación de la batería estándar española se realizó en 2016 y de la europea en 2019, quedando pendiente valorar la inclusión de alérgenos emergentes. Material y método Desarrollamos un estudio observacional, prospectivo y multicéntrico de los pacientes consecutivos del registro del Grupo Español de Investigación en Dermatitis y Alergia Cutánea sometidos a pruebas epicutáneas con hidroperóxido de linalool, hidroperóxido de limoneno, 2-hidroxi-etil-metacrilato, benzisotiazolinona, octilisotiazolinona, mezcla textil, metabisulfito sódico, propóleo, bronopol, mezcla de compuestas II, diazolidinil urea, imidazolidinil urea, decil glucósido y lauril glucósido, durante los años 2019 y 2020. Resultados Se analizó una muestra de 4.654 pacientes estudiados con diazolidinil urea, imidazolidinil urea y bronopol, y de 1.890 pacientes con el resto de los alérgenos. El índice MOAHLFA fue: M 30%, O 18%, A 15%, H 29%, L 6,5%, F 23%, A 68%. Siete alérgenos mostraron una frecuencia de sensibilización mayor del 1%: hidroperóxido de linalool, 2-hidroxi-etil-metacrilato, benzisotiazolinona, hidroperóxido de limoneno, mezcla textil, metabisulfito sódico y propóleo. Tres alérgenos mostraron una frecuencia de relevancia presente superior al 1%: hidroperóxido de linalool, 2-hidroxi-etil-metacrilato e hidroperóxido de limoneno; para benzisotiazolinona y mezcla textil, esta frecuencia fue de entre el 0,9 y el 1%. Conclusiones Nuestros resultados indican que debería valorarse la inclusión de siete nuevos alérgenos en la batería estándar española. Estos resultados podrían contribuir a la próxima actualización de la batería basal europea (AU)

Background Standard patch test series must be updated using objective data on allergen sensitization. The Spanish standard series was last updated in 2016 and the European series in 2019, and the inclusion of several emerging allergens needs to be evaluated. Material and methods We conducted a prospective, observational, multicenter study of consecutive patients from the registry of the Spanish Contact Dermatitis and Skin Allergy Research Group (GEIDAC) who were patch tested in 2019 and 2020 with linalool hydroperoxide, limonene hydroperoxide, 2-hydroxyethyl-methacrylate, benzisothiazolinone, octylisothiazolinone, textile dye mix (TDM), sodium metabisulfite, propolis, bronopol, Compositae mix II, diazolidinyl urea, imidazolidinyl urea, decyl glucoside, and lauryl glucoside. Results We analyzed data for 4654 patients tested with diazolidinyl urea, imidazolidinyl urea, and bronopol, and 1890 tested with the other allergens. The values for the MOAHLFA index components were 30% for male, 18% for occupational dermatitis, 15% for atopic dermatitis, 29% for hand, 6.5% for leg, 23% for face, and 68% for age > 40 years. Sensitization rates above 1% were observed for 7 allergens: linalool hydroperoxide, 2-hydroxyethyl-methacrylate, benzisothiazolinone, limonene hydroperoxide, TDM, sodium metabisulfite, and propolis. Three allergens had a current relevance rate of over 1%: linalool hydroperoxide, 2-hydroxyethyl-methacrylat, and limonene hydroperoxide. Benzisothiazolinone and TDM had a relevance rate of between 0.9% and 1%. Conclusions Our results indicate that 7 new allergens should be considered when extending the Spanish standard patch test series. The data from our series could be helpful for guiding the next extension of the European baseline series (AU)

Validation of Quantitative Structure-Activity Relationship (QSAR) and Quantitative Structure-Property Relationship (QSPR) approaches as alternatives to skin sensitization risk assessment.

The aim of this study was conducted to validate the physicochemical properties of a total of 362 chemicals [305 skin sensitizers (212 in the previous study + 93 additional new chemicals), 57 non-skin sensitizers (38 in the previous study + 19 additional new chemicals)] for skin sensitization risk assessment using quantitative structure-activity relationship (QSAR)/quantitative structure-property relationship (QSPR) approaches. The average melting point (MP), surface tension (ST), and density (DS) of the 305 skin sensitizers and 57 non-sensitizers were used to determine the cutoff values distinguishing positive and negative sensitization, and correlation coefficients were employed to derive effective 3-fold concentration (EC3 (%)) values. QSAR models were also utilized to assess skin sensitization. The sensitivity, specificity, and accuracy were 80, 15, and 70%, respectively, for the Toxtree QSAR model; 88, 46, and 81%, respectively, for Vega; and 56, 61, and 56%, respectively, for Danish EPA QSAR. Surprisingly, the sensitivity, specificity, and accuracy were 60, 80, and 64%, respectively, when MP, ST, and DS (MP+ST+DS) were used in this study. Further, MP+ST+DS exhibited a sensitivity of 77%, specificity 57%, and accuracy 73% when the derived EC3 values were classified into local lymph node assay (LLNA) skin sensitizer and non-sensitizer categories. Thus, MP, ST, and DS may prove useful in predicting EC3 values as not only an alternative approach to animal testing but also for skin sensitization risk assessment.

Evaluation of sensitization to the crude extract of Dermatophagoides farinae and its derived allergens, Der f 2 and Zen 1, in dogs with atopic dermatitis in Southern Brazil.

BACKGROUND: Atopic dermatitis is associated with the production of IgE antibodies against environmental allergens and allergens of the house dust miteDermatophagoides farinae are frequently implicated in the disease. OBJECTIVES: We aimed to observe the allergen-specific IgE against crudeD. farinae, Der f 2 and Zen 1 in dogs with atopic dermatitis and report if these dogs are in contact with material that could shelter mite allergens. METHODS: 100 dogs with clinical diagnosis of atopic dermatitis were included after exclusion of other forms of pruritic skin disease and dogs that already received specific or non-specific immunotherapy. These dogs were of different breeds and ages and they were presented at a veterinary teaching hospital and a private service of veterinary dermatology, both located in Curitiba, Southern Brazil. At the time of anamnesis, some questions were applied to know the possibility of these dogs having had contact with furniture and textile material which could shelter house dust mites. Sera samples were obtained and further analyzed by ELISA assay to measure serum IgE levels against these allergens with an established cut-off of 0.200 IgE optical density. RESULTS: The allergen-specific IgE positivity against crudeD. farinae (92 %) and Zen 1 (77 %) was higher than Der f 2 (56 %). There was a correlation in sensitization to crude D. farinae and Zen 1 that was not observed between crude D. farinae and Der f 2 and Der f 2 and Zen 1. The sensitization to D. farinae and its allergens was associated with an unrestricted exposition to furniture and textile material. CONCLUSION & CLINICAL RELEVANCE: dogs with atopic dermatitis are frequently sensitized to D. farinae and its allergens, Der f 2 and Zen 1, may be considered major allergens in these dogs. Zen 1 may be the main allergen responsible for the sensitization to crude D. farinae.

Allergic children with extremely high total IgE but no allergen identified in the initial screening panel.

BACKGROUND: High serum IgE level in atopic children usually implies a highly sensitized condition. However, there is a subgroup of atopic children for whom a specific allergen cannot be identified. In this study, we analyzed follow-up data from these children. METHODS: From March 2014 to July 2017, we recruited 14 atopic children with serum total IgE level higher than 500 Ku/L, but with no specific allergen identified by repeated MAST tests initially. Follow-up studies of specific IgE were conducted by the OPTIGEN MAST Allergy test and ImmunoCAP assays (Thermo Fisher Scientific/Phadia), while total IgE and specific IgG were measured by ImmunoCAP. RESULTS: The patients were aged from 2 to 17 y/o. The follow-up MAST tests showed significantly positive results in 10 patients. There were no significant differences in any of the clinical characteristics between the MAST-positive and MAST-negative groups. In the MAST-negative group, five allergen-specific IgE antibodies, including those for cockroach, Euroglyphus maynei, Blomia tropicalis, shrimp, and crab, were strongly predictive of negative ImmunoCAP results, according to ROC (Receiver operating characteristic curve) analysis of the AUC (Area under the Curve of ROC) (0.70-0.95), with significance set at p < 0.05. CONCLUSION: In two thirds of atopic children with a high serum IgE whose specific allergen had yet to be identified, it was possible to identify the specific MAST allergen(s) after an average follow-up of 33.2 months. For patients who still had negative results in follow-up MAST, mite DP, DF, and DM may be suitable choices for further allergen identification by ImmunoCAP.

Food antigen-specific IgE in dogs with suspected food hypersensitivity.

OBJECTIVE: Knowledge of cross-reactions in food-sensitive dogs will influence the choice of elimination diets and the long-term management of those patients. The objective of this study was to evaluate food allergen-specific IgE tests of suspected allergic dogs for concurrent positive reactions as possible evidence for cross reactions between allergens. MATERIAL AND METHODS: Results of serum IgE tests from 760 suspected allergic dogs submitted to 2 laboratories were evaluated statistically. After the tested allergens were grouped by their phylogenetic relationship, odds ratios as well as a sensitivity analysis of the odds ratios were performed to evaluate if concurrent positive IgE results to 2 allergens occurred more often than expected. RESULTS: Within related allergen pairs 27% (laboratory 1) and 72% (laboratory 2) of the pairs could be considered as associated. For the unrelated allergen pairs only 6.8% and 10.6% of the analyzed pairs were considered associated respectively. Strong correlations were shown in the group of ruminant allergens, especially beef and lamb, and grain allergens. High rates of concurrent reactions were also detected in the poultry group, especially between chicken and duck, as well as between pork and ruminant allergens, and soy and grain allergens. CONCLUSION: As our results showed not only correlations within related but also between non-related allergens, the possible relevance of carbohydrate moieties as well as panallergens for canine hypersensitivities warrants further study. Further investigations are necessary to distinguish co-sensitization from cross-reactions and determine the clinical relevance of food-specific IgE reactivity. CLINICAL RELEVANCE: Due to possible cross reactivity related allergens, especially beef and lamb as well as grain allergens, should not be used for an elimination diet to avoid false results.

American Contact Dermatitis Society Core Allergen Series: 2020 Update.

The American Contact Dermatitis Society Core Allergen series was introduced in 2013 and updated in 2017. Changes in our recommended allergens are again necessary, taking into account data from the American Contact Dermatitis Society's Contact Allergen Management Program top 100 allergens from 2018. For the updated series, we removed methyldibromoglutaronitrile and added new haptens: Lyral, Limonene, Linalool, carmine, benzyl salicylate, disperse yellow 3, jasmine, peppermint, pramoxine, shellac, and lauryl polyglucose (glucosides). These additional allergens should increase the yield of relevant positive reactions for our patients.

Expression Quantitative Trait Methylation Analysis Reveals Methylomic Associations With Gene Expression in Childhood Asthma.

BACKGROUND: Nasal (airway) epithelial methylation profiles have been associated with asthma, but the effects of such profiles on expression of distant cis-genes are largely unknown. RESEARCH QUESTION: To identify genes whose expression is associated with proximal and distal CpG probes (within 1 Mb), and to assess whether and how such genes are differentially expressed in atopic asthma. STUDY DESIGN AND METHODS: Genome-wide expression quantitative trait methylation (eQTM) analysis in nasal epithelium from Puerto Rican subjects (aged 9-20 years) with (n = 219) and without (n = 236) asthma. After the eQTM analysis, a Gene Ontology Enrichment analysis was conducted for the top 500 eQTM genes, and mediation analyses were performed to identify paths from DNA methylation to atopic asthma through gene expression. Asthma was defined as physician-diagnosed asthma and wheeze in the previous year, and atopy was defined as at least one positive IgE to allergens. Atopic asthma was defined as the presence of both atopy and asthma. RESULTS: We identified 16,867 significant methylation-gene expression pairs (false-discovery rate-adjusted P < .01) in nasal epithelium from study participants. Most eQTM methylation probes were distant (average distance, ∼378 kb) from their target genes, and also more likely to be located in enhancer regions of their target genes in lung tissue than control probes. The top 500 eQTM genes were enriched in pathways for immune processes and epithelial integrity and were more likely to have been previously identified as differentially expressed in atopic asthma. In a mediation analysis, we identified 5,934 paths through which methylation markers could affect atopic asthma through gene expression in nasal epithelium. INTERPRETATION: Previous epigenome-wide association studies of asthma have estimated the effects of DNA methylation markers on expression of nearby genes in airway epithelium. Our findings suggest that distant epigenetic regulation of gene expression in airway epithelium plays a role in atopic asthma.

Applicability of the proposed GHS subcategorization criterion for LLNA:BrdU-ELISA (OECD TG442B) to the CBA/J strain mouse.

The Globally Harmonized System of Classification and Labelling of Chemicals (GHS) is a hazard classification and communication system for providing information on the safe handling of chemicals worldwide. In this study, we evaluated the applicability of the newly proposed GHS subcategorization criterion for murine local lymph node assay:2-bromodeoxyuridine enzyme-linked immunosorbent assay (LLNA:BrdU-ELISA), Category 1A:EC1.6 ≤6%, Category 1B:EC1.6 >6%, to data derived from LLNA:BrdU-ELISA performed in the CBA/J strain mouse. Fifteen chemicals categorized in GHS hazard Category 1 sensitizers listed in the LLNA performance standard were tested by LLNA:BrdU-ELISA in the CBA/J strain mouse and were classified according to the new criterion. The results revealed that all of the GHS 1A or 1B category chemicals classified according to the EC3 values derived from radioisotopic LLNA (LLNA-RI) could be correctly assigned into the respective 1A and 1B categories using the newly proposed GHS subclassification criterion. In addition, analysis of the correlation between the reported EC3 values and EC1.6 values derived from the LLNA:BrdU-ELISA performed in the CBA/J strain mouse confirmed the existence of a strong correlation (r = 0.9076, P < .0001). These findings suggest that the newly proposed GHS subcategorization criterion for LLNA:BrdU-ELISA is potentially applicable for practical use in GHS subcategorization.

Atopic Dermatitis: Identification and Management of Complicating Factors.

Atopic dermatitis (AD) is a chronic relapsing inflammatory skin disease, associated with impaired skin barrier function and an atopic background. Various complicating factors, such as irritants, aeroallergens, food, microbial organisms, contact allergens, sweat, and scratching can induce the development of AD symptoms. Irritants, including soap/shampoo and clothes, can cause itching and eczematous lesions. In addition, young children with AD tend to become sensitized to eggs, milk, or peanuts, while older children and adults more often become sensitized to environmental allergens, such as house dust mites (HDM), animal dander, or pollen. Serum-specific IgE levels and skin prick test reactions to food tend to show high negative predictive values and low specificity and positive predictive values for diagnosing food allergy. On the other hand, AD adult patients tend to have severe skin symptoms and exhibit high HDM-specific IgE levels. Microbial organisms, e.g., Staphylococcus aureus and Malassezia furfur, might contribute to the pathogenetic mechanisms of AD. While sweat plays a major role in maintaining skin homeostasis, it can become an aggravating factor in patients with AD. Furthermore, scratching often exacerbates eczematous lesions. Several patient-specific complicating factors are seen in most cases. The identification and management of complicating factors are important for controlling AD.

Shotgun proteomics, in-silico evaluation and immunoblotting assays for allergenicity assessment of lesser mealworm, black soldier fly and their protein hydrolysates.

Since 2018, insects have belonged the category of Novel Foods and the presence of allergens represents one of the main hazards connected to their consumption, also due to the potential cross-reactivity with Arthropoda pan-allergens. In the present work, the allergenicity assessment of black soldier fly and lesser mealworm was performed with a shotgun bottom-up proteomic approach combined with in-silico assessment, followed by IgG- and IgE-immunoblotting experiments. The peptides identified, filtered for their abundance and robustness, belonged mainly to muscle proteins, which represented the most abundant protein group. The relevant potential allergens were in-silico identified by sequence similarity to known allergens, and among them tropomyosin resulted the most abundant insect allergen. IgG-immunoblotting analysis with anti-Tropomyosin I antibodies and IgE-immunoblotting assay with serum from patient allergic to crustacean tropomyosin were performed in order to assess the immunoreactivity in both insects. The immunoassays were carried out also on protein hydrolysates extracted by treating insects with Protease from Bacillus licheniformis (1%, 60 °C, pH 7.5). While IgG-immunoblotting demonstrated the loss of immunoreactivity for both hydrolysates, IgE-immunoblotting showed a partial immunoreactivity preservation, also after hydrolysis, in the case of black soldier fly hydrolysate, and a total loss of immunoreactivity for lesser mealworm hydrolysate.

Mechanistic understanding of dendritic cell activation in skin sensitization: additional evidences to support potency classification.

Allergic contact dermatitis (ACD) is an important occupational and environmental disease caused by topical exposure to chemical allergens. In the EU, it has been calculated that 4 % of animals are used in toxicity test for the assessment of skin sensitization (Peiser et al., 2012). To come a complete replacement of animals, evaluation of relative skin sensitization potency is necessary. The identification of mechanisms influencing allergen potency requires a better understanding of molecular events that trigger cell activation. Therefore, (i) the effects of selected allergens on surface markers expression and cytokines release in contact allergen-induced cell activation were assessed, and (ii) the role of Protein Kinase C (PKC) beta activation in contact allergen-induced cell activation was investigated. The human pro-myelocytic cell line THP-1 was used as experimental model surrogate of dendritic cells. Cells were exposed to select contact allergens of different potency and cell surface marker expression (CD80, CD86, HLA-DR) was determined by flow cytometry analysis. Cytokines production (IL-6, IL-8, IL-10, IL-12p40, IL-18) was evaluated with specific sandwich ELISA. The effective contribution of PKC beta in chemical allergen-induced cell activation was assessed by Western Blot analysis (PKC beta activation) and using a specific PKC beta inhibitor (PKC beta pseudosubstrate). In addition, to investigate if contact allergens are able to induce indeed dendritic cells (DCs) maturation, THP-1 cells were differentiated to immature DC and then exposed to contact allergen of different potency. Overall, our finding provides insights into the process of sensitization and strength of cell activation associated with allergens of different potency. Results obtained suggest that contact allergens of different potency are able to induce a different degree of activation of dendritic cells maturation involved in the process of ACD.