Search Results (569)

Extracts used for allergen sensitization testing in humans are heterogeneous in composition and may contain low levels of important allergens. In contrast, there is scant information on the variability of veterinary allergen extracts. We selected two batches of extracts of Dermatophagoides farinae house dust mites from each of three different manufacturers. We observed a 3.4-fold difference in total protein content between the two extracts with the lowest and highest amounts of allergens. After electrophoresis, the band migration patterns were found to be similar between the two batches of extracts from two manufacturers and dissimilar in the third; the migration profiles were heterogeneous between manufacturers. The six extracts did not contain the same concentrations of Der f 1 and Der f 2, with fold changes between the highest and lowest concentrations measured to be 14.3× for Der f 1 and 8.0× for Der f 2. This allergen composition heterogeneity resulted in differences in ELISA seropositivity when allergic dogs had low serum concentrations of IgE against Der f 1 and Der f 2. Our findings demonstrate that, like in human allergology, allergen extracts for veterinary use are also heterogeneous in their protein content and allergen composition. This heterogeneity can impact results when determining allergen sensitizations using crude extracts. Full article

Background: Diagnosing food allergy (FA) typically involves a detailed clinical history and confirmation of allergen-specific IgE. Oral food challenges (OFCs) remain the gold standard in FA diagnosis. This study aimed to present our experience in performing OFCs in pediatric patients with particular focus on challenges performed with cow’s milk and hen’s egg. Methods: We conducted a retrospective analysis of 205 OFCs. Clinical data were evaluated and multiple logistic regression was used to identify associations between challenge outcomes, reaction severity, and comorbidities. Results: The mean age of patients was 5.7 ± 3.1 years, with 135 (65.9%) being male. The tested foods included cow’s milk protein (CMP, 103 challenges; 50.2%), hen’s egg white protein (HEWP, 84; 41.0%), peanuts (3; 1.5%), tree nuts (4; 2.0%), gluten (3; 1.5%), hen’s egg yolk (4; 2.0%), and other foods (4; 2.0%). The overall OFC failure rate was 32.2%, and five challenges (2.4%) yielded inconclusive results. The median cumulative reactive dose was 0.27 g for baked CMP and 0.58 g for baked HEWP. Most failed OFCs involved mucocutaneous symptoms (44 cases; 66.7%). Severe multisystemic reactions occurred in four patients (2.0%), all of whom required epinephrine (6.1% of positive challenges). An increased risk of OFC failure was associated with asthma (p = 0.028; 95% CI: 0.07–1.27) and multi-food allergy (p = 0.021; 95% CI: 0.14–1.67). Additionally, the coexistence of asthma and a prior history of anaphylaxis to any food was related to OFC failure (p = 0.049; 95% CI: 0.01–2.19), as was the combination of multi-food allergy and previous anaphylaxis (p = 0.043; 95% CI: 0.03–1.70). Receiver operating characteristic (ROC) curve analysis was utilized to predict outcomes of OFCs to baked milk and baked egg and determined a specific IgE (sIgE) cutoff level of 58.1 kU/L for baked milk challenges (AUC: 0.77; sensitivity: 0.588; specificity: 0.882), and 11.3 kU/L for baked egg challenges (AUC: 0.66; sensitivity: 0.692; specificity: 0.607). Conclusions: Our findings confirm that OFCs are a safe and effective tool for diagnosing FA in children. With appropriate patient selection, the risk of severe reactions remains low. Nonetheless, comorbidities such as asthma and multi-food allergy are associated with an increased likelihood of OFC failure. Full article

Allergic contact dermatitis (ACD) is a frequent inflammatory skin disease that evolves upon exposure to contact allergens in sensitized individuals. Both the adaptive and innate immune system play pivotal roles in the pathogenesis of ACD. While the importance of T cells is undisputed, the relevance of B lymphocytes is less clear. The published data support a critical role for NFATc1 in B cell activation. Therefore, we investigated the impact of NFATc1 on B cell function during murine contact hypersensitivity (CHS), the mouse model for human ACD. Compared with wild-type mice, B cell-specific ablation of NFATc1 (Nfatc1^f/f x mb1-cre) resulted in significantly diminished CHS responses measured by ear thickness (0.81 ± 0.02 mm vs. 0.48 ± 0.02 mm (p = 0.0007)) to the obligate contact allergen 2,4,6-trinitrochlorobenzene, accompanied by a marked increase in the frequency of IL-10-producing regulatory B cells. Flow cytometric analysis showed that IL-4- and IL-17-producing CD4⁺ T cells were reduced, while IFN-γ-producing CD4⁺ T cells were marginally increased in Nfatc1^f/f x mb1-cre mice. In conclusion, NFATc1 mediates CHS responses by modulating the development of IL-10-producing B cells. These findings support the compelling notion that targeting NFATc1 may represent a potential therapeutic strategy for allergic responses. Full article

Food allergy represents a prevalent immunological disorder, with current clinical management primarily emphasizing allergen avoidance and emergency pharmacological intervention. Eucommia ulmoides polysaccharides, the principal bioactive constituents of the traditional Chinese medicinal plant Eucommia ulmoides, have demonstrated anti-inflammatory and antioxidant properties; however, their specific effects on food allergies remain inadequately characterized. A total of thirty-six female BALB/c mice were randomly allocated into three groups (n = 12 per group): the control group (CON group, receiving saline treatment), the allergic model group (OVA group, subjected to ovalbumin sensitization), and the intervention group (OVA+PS group, undergoing OVA sensitization followed by Eucommia ulmoides polysaccharides administration via gavage). The anti-allergic efficacy of Eucommia ulmoides polysaccharides was comprehensively evaluated through clinical allergy symptom scoring, histological and pathological tissue analysis, real-time fluorescence quantitative PCR (qRT-PCR) for the assessment of key gene expression, and 16S rDNA sequencing. The findings indicated the following: (1) The allergy scores in the OVA+PS group were significantly lower than those in the OVA group (p < 0.01). Following OVA stimulation, the rectal temperature of mice in the OVA group decreased sharply, whereas the temperature decline in the OVA+PS group was more gradual compared to the model group. (2) The liver, kidney, spleen, and intestinal tissues of mice in the OVA+PS group exhibited normal morphology, consistent with the CON group, which suggests that Eucommia ulmoides polysaccharides effectively mitigates the local inflammatory response induced by food allergy. (3) The expression of NICD in the spleen of mice in the OVA+PS group was significantly higher than in the OVA group (p < 0.05), while the expression of the Hes1 gene was significantly elevated in the OVA group compared to both the CON and OVA+PS groups (p < 0.05). In the OVA group, the expression level of Gata-3 was significantly elevated compared to both the CON group and the OVA+PS group (p < 0.05). Similarly, the expression of STAT5 in the OVA group was markedly higher than in the other groups (p < 0.05). (4) Eucommia ulmoides polysaccharides were found to modulate the intestinal microbiota composition in allergic mice, notably increasing the expression abundance of Enterobacter, Oscillibacter, and Butyricicoccus, while decreasing the expression abundance of Clostridium sensu stricto 1 and Turicibacter. (5) There was a correlation between alterations in the intestinal microbiota of mice and the expression of key genes. Specifically, the relative abundance of Blautia was negatively correlated with the expression of NICD and Gata-3 genes (p < 0.05), and the relative abundance of the Lachnospiraceae_FCS020_group was negatively correlated with the expression of the Hes1 gene (p < 0.05). In conclusion, Eucommia ulmoides polysaccharides demonstrate potential in alleviating allergic symptoms, providing a scientific foundation for the development of novel natural anti-allergic functional foods. Full article

The rising prevalence of pediatric food allergies represents a growing public health concern, with hospitalizations for food-induced anaphylaxis on the rise. Early cutaneous manifestations, particularly in the setting of atopic dermatitis (AD), may indicate sensitization via the skin—a critical route for allergen exposure in early life. Pediatric food allergies can be IgE-mediated, non-IgE-mediated, or mixed, with each type presenting distinct pathophysiological and clinical features. IgE-mediated reactions often involve acute urticaria and angioedema, while non-IgE forms, such as food protein-induced enterocolitis syndrome (FPIES), manifest with delayed gastrointestinal symptoms and limited skin involvement. AD is closely linked with food allergies, both in pathogenesis and symptom exacerbation, with a high prevalence of co-occurrence. Diagnosis primarily relies on clinical evaluation, supported by testing such as skin prick testing, serum IgE, and oral food challenges, though limitations exist in sensitivity and specificity. Management emphasizes allergen avoidance, symptom control, and multidisciplinary care. While many pediatric food allergies resolve with age, others persist or present chronically, necessitating long-term strategies. Coordinated management between allergy and dermatology is key to minimizing complications and supporting better long-term outcomes for affected children. Full article

The incidence of allergic diseases has increased notably in recent years. The reasons for this increase include air pollution, diet, and infectious factors. This study aims to analyze the interactions between aeroallergens, environmental pollutants, and meteorological factors and their impact on allergenic sensitization in Toledo, Spain. An aerobiological study was conducted over the past 30 years (1994–2023) using a Burkard collector and the SEAIC (Spanish Society of Allergology and Clinical Immunology) methodology. Meteorological data were obtained from the State Meteorological Agency (AEMET) and pollutant data were acquired from the Castilla-La Mancha Air Quality Monitoring Network. Patients presenting with seasonal allergic symptoms at the University Hospital of Toledo were selected for skin testing with various types of airborne pollen. A total of twenty pollen taxa were identified in the Toledo atmosphere, as follows: Cupressaceae (26.53%); Olea europaea (21.62%); Quercus (21.12%); Poaceae (10.30%); Urticaceae (2.58%); Plantago (2.48%); Platanus (2.00%); Amaranthaceae (1.72%); Rumex (1.68%); and Morus, Pistacia, Populus, Artemisia, Fraxinus, Alnus, Carex, and Ericaceae (less than 1% each). The average temperature increased by 1.2 °C, while the level of precipitation remained stable. Among all pollutants, only a moderate increase in ozone levels was observed; however, the concentrations of particulate matter and nitrogen oxides decreased. The prevalence of pollen sensitization in allergic patients ranged from 8% for Pinus nigra to 84% for Phleum pratense. In conclusion, the rise in temperature due to climate change, coupled with high concentrations of pollutants such as ozone, can result in increased concentrations of the main types of wind-borne pollen. Thus, this can lead to a greater sensitivity to pollen and, consequently, more people becoming allergic to pollen. Full article

Frontal fibrosing alopecia (FFA) is a primary lymphocytic cicatricial alopecia characterized by progressive frontotemporal hairline recession, frequently accompanied by eyebrow and body hair loss. Once considered rare, FFA is now recognized as the most common form of scarring alopecia, predominantly affecting postmenopausal women. Although its pathogenesis remains unclear, hormonal, genetic, autoimmune, and environmental factors have been implicated. Among environmental contributors, the potential role of cosmeceuticals has received increasing attention, with particular emphasis on sunscreen and facial moisturizers. Patch testing has identified sensitization to allergens frequently found in these products. However, due to numerous limitations in the existing studies, the association between cosmeceuticals and FFA remains controversial. As the prevalence of FFA continues to rise alongside widespread cosmetic product use, understanding their potential role in disease pathogenesis is essential. Current findings highlight the need for further investigation into environmental triggers. Full article

Orange allergy is estimated to account for up to 3–4% of food allergies. Major allergens identified in orange (Citrus sinensis) include Cit s 1 (germin-like protein) and Cit s 2 (profilin), while Cit s 3 (non-specific lipid transfer protein, nsLTP) and Cit s 7 (gibberellin-regulated protein) have also been described. The objective of this study was to investigate the presence and IgE-binding capacity of germin-like proteins in citrus fruits other than oranges. We describe five patients with immediate allergic reactions after orange ingestion. All patients underwent skin prick tests (SPT) to aeroallergens and common food allergens, prick-by-prick testing with orange, lemon, and mandarin (pulp, peel, seeds), total IgE, specific IgE (sIgE), anaphylaxis scoring (oFASS), and the Food Allergy Quality of Life Questionnaire (FAQLQ-AF). Protein extracts from peel and pulp of orange, lemon, and mandarin were analyzed by Bradford assay, SDS-PAGE, and IgE immunoblotting using patient sera. Selected bands were identified by peptide mass fingerprinting. A 23 kDa band was recognized by all five patients in orange (pulp and peel), lemon (peel), and mandarin (peel). This band was consistent with Cit s 1, a germin-like protein already annotated in the IUIS allergen database for orange but not for lemon or mandarin. Peptide fingerprinting confirmed the germin-like identity of the 23 kDa bands in all three citrus species. Germin-like proteins of approximately 23 kDa were identified as IgE-binding components in peel extracts of orange, lemon, and mandarin, and in orange pulp. These findings suggest a potential shared allergen across citrus species that may contribute to allergic reactions independent of LTP sensitization. Full article

Allergic contact dermatitis (ACD) is an immunologic reaction to a dermal chemical exposure that, once triggered in an individual, will result in an allergic response following subsequent encounters with the allergen. Air Force epidemiological consultations have indicated that aircraft structural maintenance workers may experience ACD at elevated rates compared to other occupations. We aimed to better understand the utility of non-animal testing methods in characterizing the sensitization potential of chemicals used during Air Force operations by evaluating the skin sensitization hazard of Air Force-relevant chemicals using new approach methodologies (NAMs) in a case study. We also evaluated the use of NAM data to develop preliminary candidate surface guidelines (PCSGs, maximum concentrations of chemicals on workplace surfaces to prevent induction of dermal sensitization) for chemicals identified as sensitizers. NAMs for assessing skin sensitization, including in silico models and experimental assays, were leveraged into an integrated approach to predict sensitization hazard for 19 chemicals. Local lymph node assay effective concentration values were predicted from NAM assay data via previously published quantitative models. The derived values were used to calculate PCSGs, which can be used to compare the presence of these chemicals on work surfaces to better understand the risk of Airmen developing ACD from occupational exposures. Full article

Biotin (vitamin B7) is a common, naturally occurring water-soluble vitamin. It belongs to the broad group of B vitamins. It is a common ingredient in dietary supplements, cosmetics, medicines, and parapharmaceutical preparations administered orally or applied topically (to the skin, hair, nails). The problem of the relationship between vitamin B supplementation and sensitivity seems to be multi-threaded. There is little literature data that would confirm that oral vitamin B supplementation or local exposure to biotin is a significant sensitizing factor. Moreover, it seems that allergy to vitamin B7 is very rare. It is possible, however, that the relationship between biotin and hypersensitivity is not limited to its direct action, but results from its essential metabolic function. Vitamin B7, as a cofactor of five carboxylases, affects the main pathways of cellular metabolism. Both deficiency and excess of biotin can result in metabolic disorders, which can have a significant impact on the homeostasis of the entire organism, including the efficient functioning of the immune system. Dysregulation of immune systems leads to its dysfunctional functioning, which can also lead to sensitization to various environmental antigens (allergens). Biotin is also used as an element of some methodological models in immunochemical tests (in vitro diagnostics), including methods used to measure the concentration of immunoglobulin E (IgE), both total (tIgE) and allergen-specific (sIgE). For this reason, vitamin B7 supplementation can be a significant interfering factor in some immunochemical tests, which can lead to false laboratory test results, both false positive and false negative, depending on the test format. This situation can have a direct impact on the quality and effectiveness of diagnostics in various clinical situations, including allergy diagnostics. This review focuses on the role of biotin in allergic reactions, both as a causative factor (allergen/hapten), a factor predisposing to the development of sensitization to various allergens, and an interfering factor in immunochemical methods used in laboratory diagnosis of hypersensitivity reactions and how it can be prevented. Full article

Asthma, the most common chronic respiratory condition in children, involves airway inflammation, hyper-responsiveness, and frequent exacerbation that worsen the airflow and inflammation. Exosomes, extracellular vesicles carrying microRNAs (miRNAs), play a key role in cell communication alongside other types of communication and are promising markers of asthma severity. This study compares exosomal miRNA and long non-coding RNA (lncRNA) profiles in boys with asthma, focusing on differences between those with normal lung functions and those with severe airflow obstruction. This study enrolled 20 boys aged 9–18 years with asthma, split into two groups based on their lung function. Ten had normal lung function (NLF; FEV1/FVC > 0.84, FEF75% > 69% predicted), while ten had severe airflow obstruction (SAO; FEV1/FVC < 0.70, FEF75 < 50% predicted). Saliva and blood samples were collected. Exosomes were isolated, quantified, and analyzed via small RNA sequencing to identify differentially expressed (DE) miRNA and lncRNA profiles. Bioinformatic tools were then used to explore potential miRNA biomarkers linked to asthma severity. SAO subjects were more likely to exhibit allergen sensitization, higher IgE levels, and more eosinophils. We identified 27 DE miRNAs in plasma and 40 DE miRNAs in saliva. Additionally, five key miRNAs were identified in both saliva and plasma which underline important pathways such as neurotrophins, T-cell receptor, and B-cell receptor signaling. We further outlined key features and functions of miRNAs and long non-coding RNAS (lncRNAs) and their interactions in children with asthma. This study identified DE miRNAs and lncRNAs in children with SAO when compared to those with NLF. Exosomal miRNAs show strong potential as non-invasive biomarkers for personalized asthma diagnosis, treatment, and monitoring. These RNA markers may also aid in tracking disease progression and response to therapy, thereby supporting the need for future studies aimed at applications in precision medicine. Full article

The diagnosis of allergic diseases and anaphylaxis is complex and encompasses a broad spectrum of in vitro and in vivo diagnostic tests. The choice of diagnostic tests is related to the presumed pathophysiological mechanism of the allergic reaction. In the past decade the implementation of component-resolved diagnostics (CRD) into clinical practice has significantly improved the depicting of sensitization profiles, which has aided in the assessment of clinically relevant allergen components that are associated with true allergy, as well as the levels of risk of severe anaphylactic reactions. Recently, multiplex-specific immunoglobulin E (IgE) platforms have emerged for better selection of patients at risk for anaphylaxis and have improved the selection criteria for patients undergoing allergen immunotherapy, including novel regimes such as oral immunotherapy. This review describes the advantages of the utilization of component-resolved diagnostics and multiplex assays in clinical settings, especially in cases of anaphylaxis when no clear trigger is recognized or where multiple culprits are suspected. As multiplex component-resolved diagnostics becomes more readily available globally and with the use of novel approaches, CRD will certainly be a crucial tool in personalized and individually tailored management plans and reduce the financial burden of anaphylaxis. Full article

IgG antibodies, signaling via the inhibitory receptor, FcγRIIb, are potent inhibitors of IgE-mediated mast cell activation. We have previously reported that in addition to blocking mast cell degranulation, inhibitory IgG signals shut down a proinflammatory transcriptional program in which mast cells produce cytokines and chemokines known to drive type 2 tissue inflammation. To determine whether such effects of allergen-specific IgG can modulate allergic inflammation in vivo, we examined the airways of mice sensitized to ovalbumin (OVA) by intraperitoneal injection and then challenged with intranasal OVA. Pretreatment with allergen-specific IgG significantly reduced the recruitment of inflammatory cells, including macrophages and eosinophils, into the lungs of OVA-sensitized mice. The bronchoalveolar lavage fluid of OVA-challenged mice contained elevated levels of chemokine ligands (CCL2 and CCL24) and interleukin-5, a response that was markedly blunted in animals receiving allergen-specific IgG. IgG-treated animals exhibited attenuated allergen-induced production of IgE, IL-4, and IL-13, along with impaired OVA-induced goblet cell hyperplasia and Muc5ac expression and suppressed airway hyperresponsiveness, consistent with a shift away from a Th2 response. Using mice with a lineage-specific deletion of FcγRIIb, we demonstrated that each of these protective effects of IgG was dependent upon the expression of this receptor on mast cells. Overall, our findings establish that allergen-specific IgG can reduce allergen-driven airway inflammation and airway hyperresponsiveness and point to a mechanistic basis for the therapeutic benefit of aeroallergen-specific IgG therapy. Full article

In recent years, grain-free pet food has gained increasing attention due to its widespread promotion as a natural and hypoallergenic diet. This trend has prompted us to conduct an in-depth critical assessment of the nutritional implications of such diets. This review systematically analyzed the nutritional components of commercially available grain-free pet food, revealing significant variability in the nutritional composition of commercial pet diets. Moreover, grain-free formulations typically exhibit higher protein and fat levels. On the other hand, this review further explores the multifaceted health impacts of these diets on pets, including digestive function, cardiovascular health, allergic reactions, blood sugar regulation, mycotoxin safety, and palatability. This review points out that grain-free diets may offer potential benefits, such as improved blood sugar control, reduced mycotoxin exposure, and enhanced palatability; however, they also pose clear risks, particularly the potential association with dilated cardiomyopathy (DCM) in dogs. Additionally, the presence or absence of grains in the diet does not mitigate the risk of allergies. A grain-free diet is only intended to help specific individuals (such as those who are sensitive to grains/gluten) avoid allergens. Ultimately, the review emphasizes that nutritional adequacy, balance, and meeting individualized needs are the cornerstones of pet health, aiming to provide valuable insights for pet caregivers, veterinarians, and researchers. Full article

Allergic diseases, particularly respiratory allergies like asthma and allergic rhinitis, are a growing public health concern influenced by environmental factors such as climate change and air pollution. The exposome framework enables a comprehensive assessment of how lifelong environmental exposures shape immune responses and allergic sensitization. Peru’s diverse ecosystems and climates provide a unique setting to investigate regional variations in allergic sensitization. This study characterized these patterns in five Peruvian regions with distinct climatic, urbanization, and socioeconomic characteristics. A total of 268 individuals from Lima, Piura, Tarapoto, Arequipa, and Tacna were analysed for allergen-specific IgE responses using a multiplex IgE detection system. The results revealed significant geographical differences in sensitization frequencies and serodominance profiles, based on descriptive statistics and supported by Chi-square comparative analysis. House dust mites were predominant in humid regions, while Arequipa exhibited higher sensitization to cat allergens. In Tacna, olive pollen showed notable prevalence alongside house dust mites. Tarapoto’s high humidity correlated with increased fungal and cockroach allergen sensitization. Notably, some allergens traditionally considered minor, such as Der p 5 and Der p 21, reached sensitization prevalences close to or exceeding 50% in certain regions. These findings provide the most detailed molecular characterization of allergic sensitization in Peru to date, highlighting the importance of region-specific allergy management strategies. Understanding environmental influences on allergic diseases can support more effective diagnostic, therapeutic, and preventive approaches tailored to diverse geographical contexts. Full article