Toward Consensus Epitopes B and T of Tropomyosin Involved in Cross-Reactivity across Diverse Allergens: An In Silico Study

Tropomyosin (TM) is a pan-allergen with cross-reactivity to arthropods, insects, and nematodes in tropical regions. While IgE epitopes of TM contribute to sensitization, T-cell (MHC-II) epitopes polarize the Th2 immune response. This study aimed to identify linear B and T consensus epitopes among house dust mites, cockroaches, Ascaris lumbricoides, shrimp, and mosquitoes, exploring the molecular basis of cross-reactivity in allergic diseases. Amino acid sequences of Der p 10, Der f 10, Blo t 10, Lit v 1, Pen a 1, Pen m 1, rAsc l 3, Per a 7, Bla g 7, and Aed a 10 were collected from Allergen Nomenclature and UniProt. B epitopes were predicted using AlgPred 2.0 and BepiPred 3.0. T epitopes were predicted with NetMHCIIpan 4.1 against 10 HLA-II alleles. Consensus epitopes were obtained through analysis and Epitope Cluster Analysis in the Immune Epitope Database. We found 7 B-cell epitopes and 28 linear T-cell epitopes binding to MHC II. A unique peptide (residues 160-174) exhibited overlap between linear B-cell and T-cell epitopes, highly conserved across tropomyosin sequences. These findings shed light on IgE cross-reactivity among the tested species. The described immuno-informatics pipeline and epitopes can inform in vitro research and guide synthetic multi-epitope proteins' design for potential allergology immunotherapies. Further in silico studies are warranted to confirm epitope accuracy and guide future experimental protocols.

Recombinant PreS-fusion protein vaccine for birch pollen and apple allergy

BACKGROUND

IgE cross-sensitization to major birch pollen allergen Bet v 1 and pathogenesis-related (PR10) plant food allergens is responsible for the pollen-food allergy syndrome.

METHODS

We designed a recombinant protein, AB-PreS, consisting of non-allergenic peptides derived from the IgE-binding sites of Bet v 1 and the cross-reactive apple allergen, Mal d 1, fused to the PreS domain of HBV surface protein as immunological carrier. AB-PreS was expressed in E. coli and purified by chromatography. The allergenic and inflammatory activity of AB-PreS was tested using basophils and PBMCs from birch pollen allergic patients. The ability of antibodies induced by immunization of rabbits with AB-PreS and birch pollen extract-based vaccines to inhibit allergic patients IgE binding to Bet v 1 and Mal d 1 was assessed by ELISA.

RESULTS

IgE-binding experiments and basophil activation test revealed the hypoallergenic nature of AB-PreS. AB-PreS induced lower T-cell activation and inflammatory cytokine production in cultured PBMCs from allergic patients. IgG antibodies induced by five injections with AB-PreS inhibited allergic patients' IgE binding to Bet v 1 and Mal d 1 better than did IgG induced by up to 30 injections of six licensed birch pollen allergen extract-based vaccines. Additionally, immunization with AB-PreS induced HBV-specific antibodies potentially protecting from infection with HBV.

CONCLUSION

The recombinant AB-PreS-based vaccine is hypoallergenic and superior over currently registered allergen extract-based vaccines regarding the induction of blocking antibodies to Bet v 1 and Mal d 1 in animals.

Multiplexed transcriptional profiling of Dermatophagoides house dust mites allergens in human epithelium cells

Allergic asthma, a chronic disease characterized by airway inflammation, poses a significant public health concern. It is well-established that house dust mites (HDMs) are common inducers of allergic responses in individuals, particularly children. In central Taiwan, our research team observed that over 80% of allergic children exhibited sensitization to various HDMs species. This investigation aims to bridge the gap between these observations and a better understanding of the early fundamental mechanisms for preventing allergic diseases. Specifically, our study delves into the impact of crude extracts of HDMs on human epithelial BEAS-2B cells. Our findings, based on RNA sequencing (RNA-seq) analysis, shed light on how three major Dermatophagoides HDMs allergens activate a common Toll-like receptor signaling pathway in human epithelial cells within a 4-h treatment. During this process, the nuclear transcription factor NF-κB translocated into the cell nucleus within 30 min of allergen stimulation, triggering the expression of pro-inflammatory genes such as IL-6 and IL-8 over 4 h. Additionally, when the cells were treated with specific Dermatophagoides microceras (Der m) allergens, it resulted in the upregulation of genes that regulate type 1 diabetes mellitus (T1DM) signaling pathways. This led to the mediation of IL-12A inflammation. Furthermore, there was an increase in gene sets associated with cilia function and the microtubule cytoskeleton in human epithelial cells after treatment with a combination of Der m allergens and Dexamethasone. Additionally, OMICs analysis was conducted to examine the effects of HDMs allergenic stimulation on human epidermal cells. We aimed to improve our understanding of the molecular mechanisms within cells and identify potential targets and natural products in the treatment of asthma caused by HDMs allergens.

Gene editing in allergic diseases: Identification of novel pathways and impact of deleting allergen genes

Gene editing technology has emerged as a powerful tool in all aspects of health research and continues to advance our understanding of critical and essential elements in disease pathophysiology. The clustered regularly interspaced short palindromic repeats (CRISPR) gene editing technology has been used with precision to generate gene knockouts, alter genes, and identify genes that cause disease. The full spectrum of allergic/atopic diseases, in part because of shared pathophysiology, is ripe for studies with this technology. In this way, novel culprit genes are being identified and allow for manipulation of triggering allergens to reduce allergenicity and disease. Notwithstanding current limitations on precision and potential off-target effects, newer approaches are rapidly being introduced to more fully understand specific gene functions as well as the consequences of genetic manipulation. In this review, we examine the impact of editing technologies of novel genes relevant to peanut allergy and asthma as well as how gene modification of common allergens may lead to the deletion of allergenic proteins.

Evaluation of anti-Fel d 1 IgY ingredient for pet food on growth performance in kittens

Introduction

The domestic cat (Felis catus) is one of the most common pets. Worldwide, approximately one in five adults are sensitive to cat allergens. The major cat allergen is the secretoglobulin Fel d 1, which is primarily produced in the salivary and sebaceous glands. Chickens produce IgY antibodies, which are similar in structure to mammalian IgG. When chickens are exposed to Fel d 1, anti-Fel d 1-specific IgY (AFD1) is produced and is naturally concentrated in egg yolk. The aim of this study was to evaluate the tolerability, effects on growth and food consumption, and potential adverse effects of a chicken egg product ingredient containing AFD1 in kittens.

Methods

This was a blinded, controlled study. Twenty-seven (27) eight-week old kittens were randomly assigned to three feeding groups containing 0 ppm AFD1 (Group 0), 8 ppm AFD1 (Group 1), and 16 ppm AFD1 (Group 2) for 84 days. Veterinary exams and bloodwork were performed on Day 42 and Day 84, and body weight and body condition score (BCS) were monitored weekly.

Results

Throughout the study, there were no signs of nutritional deficiency or adverse clinical events in any of the subjects. Administration of a chicken egg product ingredient containing AFD1 in the diet (whether in coating or combination of coating and top dress) had no significant effect on body weight nor food consumption, and all subjects maintained a healthy Body Condition Score (BCS) throughout the study. Moreover, there were no biologically significant differences in the mean clinical chemistry and hematology parameters.

Discussion

This study demonstrated that a diet formulated to contain up to 16  ppm AFD1, included in the coating and the top-dress of dry kitten food, was well tolerated, promoted adequate growth, and exhibited no adverse effects.

Linear epitopes of bony fish β-parvalbumins

Introduction

Fish β-parvalbumins are common targets of allergy-causing immunity. The nature of antibody responses to such allergens determines the biological outcome following exposure to fish. Specific epitopes on these allergens recognised by antibodies are incompletely characterised.

Methods

High-content peptide microarrays offer a solution to the identification of linear epitopes recognised by antibodies. We characterized IgG and IgG4 recognition of linear epitopes of fish β-parvalbumins defined in the WHO/IUIS allergen database as such responses hold the potential to counter an allergic reaction to these allergens. Peripheral blood samples, collected over three years, of 15 atopic but not fish-allergic subjects were investigated using a microarray platform that carried every possible 16-mer peptide of known isoforms and isoallergens of these and other allergens.

Results

Interindividual differences in epitope recognition patterns were observed. In contrast, reactivity patterns in a given individual were by comparison more stable during the 3 years-course of the study. Nevertheless, evidence of the induction of novel specificities over time was identified across multiple regions of the allergens. Particularly reactive epitopes were identified in the D helix of Cyp c 1 and in the C-terminus of Gad c 1 and Gad m 1.02. Residues important for the recognition of certain linear epitopes were identified. Patterns of differential recognition of isoallergens were observed in some subjects.

Conclusions

Altogether, comprehensive analysis of antibody recognition of linear epitopes of multiple allergens enables characterisation of the nature of the antibody responses targeting this important set of food allergens.

Effects of increasing sensitizing doses of ovalbumin on airway hyperresponsiveness in asthmatic mice

BACKGROUND

The dosage of ovalbumin (OVA) during the sensitization stage is considered a crucial factor in the development of airway hyperresponsiveness (AHR). However, the inconsistent dosages of sensitizing OVA used in current studies and the lack of research on their impact on AHR are notable limitations.

METHODS

We examined the impact of increasing sensitizing doses of OVA in a murine asthma model, which entailed initial sensitization with OVA followed by repeated exposure to OVA aerosols. BALB/c mice were primed with doses of OVA (0, 10, 20, 50, and 100 μg) plus 1 mg Alum on Days 0 and 7, and were challenged with OVA aerosols (10 mg/mL for 30 min) between Days 14 and 17. Antigen-induced AHR to methacholine (MCh), as well as histological changes, eosinophilic infiltration, and epithelial injury were assessed.

RESULTS

The result indicated that there are striking OVA dose-related differences in antigen-induced AHR to MCh. The most intense antigen-induced AHR to MCh was observed with sensitization at 50 μg, while weaker responses were seen at 10, 20, and 100 μg. Meanwhile, there was a significant increase in eosinophil count with sensitization at 50 μg. The changes of AHR were correlated with total cells count, lymphocytes count, eosinophils count, and basophils count in bronchoalveolar lavage fluid; however, it did not correlate with histological changes such as cellular infiltration into bronchovascular bundles and goblet cell hyperplasia of the bronchial epithelium.

CONCLUSION

Overall, this study demonstrated that sensitization with 50 μg of OVA resulted in the most significant AHR compared to other dosages. These findings may offer valuable insights for future research on mouse asthma modeling protocols.

Diagnostic accuracy of patch testing based in clinical response to contact allergen restrictions in allergic contact dermatitis

Summary

Background. Patch testing (PT) is used to identify substances that cause allergic contact dermatitis (ACD). However, the clinical effects of allergen restrictions following PT have not been thoroughly investigated. This study aims to assess the diagnostic accuracy of PT in patients suspected of having ACD. Methods. Prospective study. PT were performed in patients with clinical diagnosis of ACD. Patients with a positive PT (case group) had a strict restriction of the suspected substance for one month. In patients with negative patch testing (control group), allergen restriction was based in clinical history. Clinical reduction (CR) of at least 50% in disease activity (CR50%) after one month of allergen restriction was considered clinically relevant. Total control was defined as clinical reduction of at least 90% (CR90%). Results. From 400 patients, 66.2% had a positive PT. The sensitivity of PT to identify CR50% was 84%, specificity 47%, PPV 53%, and NPV 81%. Only 10.5% of patients achieved CR90%. Conclusions. The PT had moderate diagnostic accuracy. It could be useful as a screening, but a positive result should be confirmed with controlled allergen restriction. The low number of patients who achieved a 90% CR invites to reconsider the allergens included in PT and the mechanistic processes of the disease.

Development of a mini pig model of peanut allergy

Introduction

The prevalence of peanut allergies is increasing, emphasizing the need for an animal model to enhance our understanding of peanut allergy pathogenesis and to advance diagnostic tools and therapeutic interventions. While mice are frequently used as model organisms, their allergic responses do not fully mirror those observed in humans, warranting the exploration of a higher animal model. The porcine gastrointestinal system closely resembles that of humans, and exhibits allergy symptoms akin to human responses, making pigs a promising model for peanut allergy research.

Methods

In this study we compared two allergen sensitization protocols involving either topical allergen application after repeated tape stripping (TS) or intraperitoneal (IP) injections to induce peanut-specific allergy and anaphylaxis reactions in mini pigs. Mini pigs sensitized with a combination of peanut protein extract (PE) and cholera toxin (CT) through either the IP or the TS route.

Results

Sensitized pigs via both methods developed systemic PE-specific IgG and IgE responses. Following peanut challenge via the IP route, both TS- and IP-sensitized pigs displayed allergy symptoms, including lethargy, skin rashes, vomiting, and a drop in body temperature. However, respiratory distress was observed exclusively in pigs sensitized through the TS route and not in those sensitized through the IP route. However, it is noteworthy that both groups of sensitized pigs maintained peanut hypersensitivity for up to two months post-sensitization, albeit with a reduction in the severity of allergy symptoms. Importantly, both groups exhibited sustained levels of PE-specific IgG, IgE, and elevated concentrations of mast cell protease in their blood following the IP challenges.

Discussion

Overall, this study reports TS and IP as two different modes of sensitization leading to onset of peanut specific allergic reactions in mini pigs, but only the TS-sensitization led to systemic anaphylaxis (simultaneous presence of symptoms: breathing difficulty, intense skin rash, and impaired mobility). A distinctive feature of these sensitization protocols is the 100% success rate (N = 4 pigs per group) in sensitizing the subjects.

Design of an Ara h 2 hypoallergen from conformational epitopes

INTRODUCTION

Adverse reactions are relatively common during peanut oral immunotherapy. To reduce the risk to the patient, some researchers have proposed modifying the allergen to reduce IgE reactivity, creating a putative hypoallergen. Analysis of recently cloned human IgG from patients treated with peanut immunotherapy suggested that there are three common conformational epitopes for the major peanut allergen Ara h 2. We sought to test if structural information on these epitopes could indicate mutagenesis targets for designing a hypoallergen and evaluated the reduction in IgE binding via immunochemistry and a mouse model of passive cutaneous anaphylaxis (PCA).

METHODS

X-ray crystallography characterized the conformational epitopes in detail, followed by mutational analysis of key residues to modify monoclonal antibody (mAb) and serum IgE binding, assessed by ELISA and biolayer interferometry. A designed Ara h 2 hypoallergen was tested for reduced vascularization in mouse PCA experiments using pooled peanut allergic patient serum.

RESULTS

A ternary crystal structure of Ara h 2 in complex with patient antibodies 13T1 and 13T5 was determined. Site-specific mutants were designed that reduced 13T1, 13T5, and 22S1 mAbs binding by orders of magnitude. By combining designed mutations from the three major conformational bins, a hexamutant (Ara h 2 E46R, E89R, E97R, E114R, Q146A, R147E) was created that reduced IgE binding in serum from allergic patients. Further, in the PCA model where mice were primed with peanut allergic patient serum, reactivity upon allergen challenge was significantly decreased using the hexamutant.

CONCLUSION

These studies demonstrate that prior knowledge of common conformational epitopes can be used to engineer reduced IgE reactivity, an important first step in hypoallergen design.

Microarray molecular mapping of horses with severe asthma

BACKGROUND

Severe asthma (SA) in horses, resembling human asthma, is a prevalent, debilitating allergic respiratory condition marked by elevated allergen-specific immunoglobulin E (IgE) against environmental proteins; however, research exploring the exposome's influence on IgE profiles is currently limited but holds paramount significance for diagnostic and therapeutic developments.

ANIMALS

Thirty-five sports horses were analyzed, consisting of environmentally matched samples from France (5 SA; 6 control), the United States (6 SA; 6 control), and Canada (6 SEA; 6 control).

METHODS

This intentional cross-sectional study investigated the sensitization profiles of SA-affected and healthy horses via serological antigen microarray profiling. Partial least square-discriminant analysis (PLS-DA) was used to identify and rank the importance of allergens for class separation (ie, affected/non-affected) as variable influence of projection (VIP), and allergen with commonality internationally established via frequency analysis.

RESULTS

PLS-DA models showed high discriminatory power in predicting SA in horses from Canada (area under the curve [AUC] 0.995) and France (AUC 0.867) but poor discriminatory power in horses from the United States (AUC 0.38). Hev b 5.0101, Cyn D, Der p 2, and Rum cr were the only shared allergens across all geographical groups.

CONCLUSIONS AND CLINICAL IMPORTANCE

Microarray profiling can identify specific allergenic components associated with SA in horses, while mathematical modeling of this data can be used for disease classification, highlighting the variability of sensitization profiles between geographical locations and emphasizing the importance of local exposure to the prevalence of different allergens. Frequency scoring analysis can identify important variables that contribute to the classification of SA across different geographical regions.

Assessment of crustacean allergen detection methods: cross reactivity with edible insect samples

Increased interest in consumption of insects in recent years has led to an increased focus on associated food safety concerns, and allergy is one of the most relevant. In the United States, crustacean shellfish are regulated as a major allergenic food group per the Food, Drug, and Cosmetic (FD&C) Act. Insects and crustacean shellfish are both arthropods, and clinical cross-reactivity between the two groups has been demonstrated. The goal of this work was to establish whether that clinical cross-reactivity translates into analytical cross-reactivity with detection assays targeting crustacean shellfish allergens. Edible insect samples were analyzed using four different crustacean allergen detection methods: Multi-Analyte Profiling Food Allergen Detection Assay (xMAP FADA), enzyme-linked immunosorbent assay (ELISA), western blot, and real-time polymerase chain reaction (PCR). Results indicate that the immunoassay-based xMAP FADA, ELISA, and western blot were susceptible to cross-reactivity, while the DNA-based PCR methods had minimal reactivity with insect samples. These results confirm that edible insects show analytical cross-reactivity with the immunoassays which may result in false positive detection of crustacean allergens in insect samples. Confirmation using DNA-based PCR, which shows little to no cross-reactivity, clarifies ambiguous results.

Natural human Bet v 1-specific IgG antibodies recognize non-conformational epitopes whereas IgE reacts with conformational epitopes

BACKGROUND

The nature of epitopes on Bet v 1 recognized by natural IgG antibodies of birch pollen allergic patients and birch pollen-exposed but non-sensitized subjects has not been studied in detail.

OBJECTIVE

To investigate IgE and IgG recognition of Bet v 1 and to study the effects of natural Bet v 1-specific IgG antibodies on IgE recognition of Bet v 1 and Bet v 1-induced basophil activation.

METHODS

Sera from birch pollen allergic patients (BPA, n = 76), allergic patients without birch pollen allergy (NBPA, n = 40) and non-allergic individuals (NA, n = 48) were tested for IgE, IgG as well as IgG1 and IgG4 reactivity to folded recombinant Bet v 1, two unfolded recombinant Bet v 1 fragments comprising the N-terminal (F1) and C-terminal half of Bet v 1 (F2) and unfolded peptides spanning the corresponding sequences of Bet v 1 and the apple allergen Mal d 1 by ELISA or micro-array analysis. The ability of Bet v 1-specific serum antibodies from non-allergic subjects to inhibit allergic patients IgE or IgG binding to rBet v 1 or to unfolded Bet v 1-derivatives was assessed by competition ELISAs. Furthermore, the ability of serum antibodies from allergic and non-allergic subjects to modulate Bet v 1-induced basophil activation was investigated using rat basophilic leukaemia cells expressing the human FcεRI which had been loaded with IgE from BPA patients.

RESULTS

IgE antibodies from BPA patients react almost exclusively with conformational epitopes whereas IgG, IgG1 and IgG4 antibodies from BPA, NBPA and NA subjects recognize mainly unfolded and sequential epitopes. IgG competition studies show that IgG specific for unfolded/sequential Bet v 1 epitopes is not inhibited by folded Bet v 1 and hence the latter seem to represent cryptic epitopes. IgG reactivity to Bet v 1 peptides did not correlate with IgG reactivity to the corresponding Mal d 1 peptides and therefore does not seem to be a result of primary sensitization to PR10 allergen-containing food. Natural Bet v 1-specific IgG antibodies inhibited IgE binding to Bet v 1 only poorly and could even enhance Bet v 1-specific basophil activation.

CONCLUSION

IgE and IgG antibodies from BPA patients and birch pollen-exposed non-sensitized subjects recognize different epitopes. These findings explain why natural allergen-specific IgG do not protect against allergic symptoms and suggest that allergen-specific IgE and IgG have different clonal origin.

Component-resolved diagnosis in childhood and prediction of asthma in early adolescence: A birth cohort study

INTRODUCTION

Component-resolved diagnosis (CRD) has been decisive in exploring the mechanisms of IgE sensitization, but the predictive ability to detect asthma has not been addressed. We aim to develop and evaluate the performance of a personalized predictive algorithm for asthma that integrates information on allergic sensitization using CRD.

METHODS

One thousand one hundred one twenty-five children from the Generation XXI birth cohort were randomly selected to perform a screening test for allergic sensitization and a subsample was characterized using CRD against 112 allergen components. Allergen components were analyzed using volcano plots and partial least squares (PLS) analysis. Logistic regression was performed to assess the associations between the obtained latent components (LC) and allergic outcomes (asthma, rhinitis, eczema) including other potential predictors used in previous asthma risk scores. The accuracy of the model in predicting asthma was assessed using Receiver Operating Characteristic (ROC) curve statistics.

RESULTS

In the PLS, the first LC was positively associated with asthma, rhinitis, and eczema. This LC was mainly driven by positive weights for Der p 1/2/23, Der f 1/2, and Fel d 1. The main components in the second LC were pollen and food allergens. History of early wheezing and parental allergy were included in the predictive model and the area under the curve improved to 0.82.

CONCLUSIONS

This is the first approach to improve the clinical applicability of CRD by combining CRD and clinical data to predict asthma at 13 years. Sensitization to distinct allergen molecules seems relevant to improve the accuracy of asthma prediction models.

Prevalence and Socioeconomic Impact of Allergic Rhinitis Among Ear, Nose, and Throat Patients of a Tertiary Hospital

OBJECTIVES

The objectives of this study were to establish the demographic factors of allergic rhinitis patients taking part in the study, to gain insight into the common symptoms experienced by patients with allergic rhinitis, to know the common allergens or triggers that lead to the symptoms of allergic rhinitis and to determine the prevalence of other comorbidities associated with allergic rhinitis.

METHODS

The study was a cross-sectional hospital-based study encompassing both quantitative and qualitative features of the participants involved. The quantitative study involved collecting data on allergic rhinitis clients visiting our tertiary hospital, over the period of March 1, 2021, to June 25, 2021. The quantitative data included the gender and age groups commonly affected, the most common symptom, and the trigger identified. Whilst, the qualitative aspect of the study involved the socioeconomic impact of allergic rhinitis on the clients.

RESULTS

The prevalence of allergic rhinitis is 10% at the ENT clinic of our hospital. It was most common in the age group (19-35). Urban residents suffered more from allergic rhinitis than the rural residents. The main presenting complaint was sneezing and the commonest comorbid condition and trigger associated with allergic rhinitis were sinusitis and dust mites respectively. Twenty-nine percent of respondents had experienced reduced productivity at their workplace and in school. Twenty-one percent had experienced depression while 26% perceived the cost of treatment to be greatly expensive. The use of face masks was found not to be beneficial in reducing the symptoms of allergic rhinitis in most clients.

CONCLUSION

The conclusions reached at the end of this study were that the public must be educated on allergic rhinitis and to look out for the triggers, signs, and symptoms of it and then report early to the hospital for appropriate management.

Pulsed electric field treatment of soymilk: Impact on Kunitz trypsin inhibitor allergenicity, antinutritional factor, and aroma characteristics

Allergens, antinutritional factors, and lipoxygenase (LOX) enzyme present in soymilk limit its consumption as vegan milk. Therefore, the present study focuses on reducing these limiting factors using pulsed electric field (PEF) treatment. In this regard, 20-40 kV/cm electric field was applied to soymilk for the effective treatment periods of 450, 1350, and 2250 ms. After the treatment, a reduction in pH (6.60 ± 0.10 to 6.47 ± 0.12) and an increase in the conductivity (173.03 ± 0.40 to 177.33 ± 0.72 µS) were observed. Furthermore, FTIR (Fourier Transform Infrared Spectroscopy), UV (Ultra Violet) intrinsic spectra, and CD (Circular Dichroism) spectra (α-helix reduction and β-sheet increase) data indicated mild structural changes in the proteins of soymilk. As a result, PEF treatment reduced the soymilk allergenicity (67.33 ± 20.48%), LOX activity (69.45 ± 9.38%), and trypsin inhibitor activity (75.61 ± 4.04%). Apart from that, the color, viscosity, and volatiles of soymilk also had significant changes due to PEF treatment. The aroma changes in PEF-treated soymilk were highly influenced by two major principal component (PC1 & PC2) groups and they accounted for about 70% of the aroma variations. However, these changes were mild and did not induce any off-flavors and the treatment remained effective against the quality hazards like allergens, antinutritional factors, and LOX enzyme. PRACTICAL APPLICATION: PEF treatment of soymilk reduces the possible allergic reactions in human body at least by 30%. Further, it reduces the antinutritional factor and off-odor inducing compounds. Therefore, the PEF treatment can be used in industries as a pre-treatment to produce allergen and antinutritional compounds free protein isolates from soybeans.

Grandmaternal allergen sensitization reprograms epigenetic and airway responses to allergen in second-generation offspring

Asthma susceptibility is influenced by environmental, genetic, and epigenetic factors. DNA methylation is one form of epigenetic modification that regulates gene expression and is both inherited and modified by environmental exposures throughout life. Prenatal development is a particularly vulnerable time period during which exposure to maternal asthma increases asthma risk in offspring. How maternal asthma affects DNA methylation in offspring and what the consequences of differential methylation are in subsequent generations are not fully known. In this study, we tested the effects of grandmaternal house dust mite (HDM) allergen sensitization during pregnancy on airway physiology and inflammation in HDM-sensitized and challenged second-generation mice. We also tested the effects of grandmaternal HDM sensitization on tissue-specific DNA methylation in allergen-naïve and -sensitized second-generation mice. Descendants of both allergen- and vehicle-exposed grandmaternal founders exhibited airway hyperreactivity after HDM sensitization. However, grandmaternal allergen sensitization significantly potentiated airway hyperreactivity and altered the epigenomic trajectory in second-generation offspring after HDM sensitization compared with HDM-sensitized offspring from vehicle-exposed founders. As a result, biological processes and signaling pathways associated with epigenetic modifications were distinct between lineages. A targeted analysis of pathway-associated gene expression found that Smad3 was significantly dysregulated as a result of grandmaternal allergen sensitization. These data show that grandmaternal allergen exposure during pregnancy establishes a unique epigenetic trajectory that reprograms allergen responses in second-generation offspring and may contribute to asthma risk.NEW & NOTEWORTHY Asthma susceptibility is influenced by environmental, genetic, and epigenetic factors. This study shows that maternal allergen exposure during pregnancy promotes unique epigenetic trajectories in second-generation offspring at baseline and in response to allergen sensitization, which is associated with the potentiation of airway hyperreactivity. These effects are one mechanism by which maternal asthma may influence the inheritance of asthma risk.

High plasma IL-6 levels may enhance the adverse effects of mouse allergen exposure in urban schools on asthma morbidity in children

BACKGROUND

Few data on the relationships between environmental exposures, asthma morbidity, and systemic IL-6 inflammation exist.

OBJECTIVE

We sought to determine whether baseline plasma IL-6 level is associated with increased asthma morbidity in children exposed to mouse allergen in inner-city classrooms.

METHODS

Data from the longitudinal School Inner-City Asthma Studies of 215 children with asthma, aged 4 to 14 years and recruited from urban elementary schools, were analyzed. Given the unknown threshold of IL-6 risk levels and skewness of the distribution, the children were stratified into tertiles as follows: low baseline IL-6 level (<0.013 pg/mL), moderate baseline IL-6 level (0.013-0.302 pg/mL), and high baseline IL-6 level (>0.302 pg/mL). Relationships between plasma IL-6 level and body mass index (BMI) percentile, inflammatory markers, lung function, mouse allergen exposure, and asthma outcomes were assessed.

RESULTS

Cross-sectional analysis demonstrated that increasing IL-6 level was associated with higher BMI percentile (P < .0001), C-reactive protein level (P = .0006), and blood neutrophil count (P = .0024). IL-6 was not associated with type 2 inflammatory markers, including blood eosinophil count, allergic sensitization, or fractional exhaled nitric oxide level. Longitudinal analysis showed that children with high IL-6 levels had a higher number of days with asthma symptoms than did those children with moderate (incidence rate ratio = 1.74 [95% CI = 1.10-2.77]; P = .0187) or low (incidence rate ratio =1.83 [95% CI = 1.21-2.77]; P = .0043) IL-6 levels. Children with high IL-6 levels who were exposed to increasing levels of mouse allergen exhibited lower ratios of FEV1 value to forced vital capacity than did children with moderate IL-6 levels (β = -0.0044 [95% CI = -0.0073 to -0.0015]; pairwise interaction P = .0028) or low IL-6 levels (β = -0.0042 [95% CI = - 0.0070 to -0.0013]; pairwise interaction P = .0039).

CONCLUSIONS

Inner-city children with asthma and high plasma IL-6 levels are more likely to have an increased BMI, elevated C-reactive protein level, elevated blood neutrophil count, and greater asthma symptoms. High IL-6 level appears to increase susceptibility to the effects of classroom exposure to mouse allergen on lung function in urban children.

The epidemiology of food allergy in primary care clinic: A cross-sectional study

Food allergy (FA) is an increasing global public health concern. Little is known about FA counsel in primary care clinics. The objective of this study is to describe the characteristics of FA in primary care clinics. It also aims to report the national primary care physicians' current knowledge and practices. An electronic cross-sectional questionnaire was distributed to primary care physicians working at the Ministry of Health primary care clinics, across Kuwait's' 6 health districts, between May and June 2023. The questionnaire was made of 3 sections: participants' demographic, FA counsel characteristics, participants' knowledge and practices during FA counsel, and 37 variable tools. Eight-seven percent of primary care physicians counseled a patient with FA within the last 12 months. Most FA patients were children and infants. Approximately 2 out of 10 primary physicians counseled > 1 FA case/week. Prevalence of clinical presentation was: angioedema (23%), many skin hives (21%), few skin hives (19%), and mouth itch (9.4%). Prevalence of allergens was; peanuts (46%), shellfish (37%), eggs (36%), and tree nuts (36%), respectively. The mean of primary care physicians' correct answers about FA was 58% and only 26% of primary care physicians acquired a sufficient amount of knowledge about FA, scoring above 67%. Their Knowledge scores about FA: clinical presentation 7 ± 1.6, diagnostic tests 2 ± 1, treatment 2.6 ± 1, and prevention 3 ± 1. In practice, correct treatment was offered by 30% of physicians, and 55% made the right referrals 86% are longing for training about FA. FA is a common counsel in primary care clinics. The most common FA presentation is a severe allergic reaction in the pediatric population. The current primary care physicians have insufficient knowledge about counseling FA and long for further training. Collectively, protocols and training for FA counseling should be launched in primary care.

Structural Similarities, in Relation with the Cross-Reactivity, of Hymenoptera Allergenic Dipeptidyl Peptidases IV-An Overall Comparison Including a New Dipeptidyl Peptidase IV Sequence from Vespa velutina

(1) Background: Dipeptidyl Peptidases IV (DPPIVs), present in many organisms, are minor components in the venoms of Hymenoptera, where they have been identified as cross-reactive allergenic molecules. Considering that the structure of homologous DPPIVs is well characterized, we aimed to explain which regions have higher similarity among these proteins and present a comparison among them, including a new Vespa velutina DPPIV sequence. Moreover, two cases of sensitization to DPPIVs in wasp- and honeybee-sensitized patients are presented. (2) Methods: Proteomic analyses have been performed on the venom of the Asian hornet Vespa velutina to demonstrate the sequence of its DPPIV (allergen named Vesp v 3, with sequence accession number P0DRB8, and with the proteomic data available via ProteomeXchange with the identifier PXD046030). A comparison performed through their alignments and analysis of the three-dimensional structure showed a region with higher similarity among Hymenoptera DPPIVs. Additionally, ImmunoCAP™ determinations (including specific inhibition experiments), as well as IgE immunoblotting, are performed to demonstrate the allergenicity of Api m 5 and Ves v 3. (3) Results and Conclusions: The data presented demonstrate that the similarities among Hymenoptera DPPIVs are most likely localized at the C-terminal region of these enzymes. In addition, a higher similarity of the Vespa/Vespula DPPIVs is shown. The clinical cases analyzed demonstrated the allergenicity of Api m 5 and Ves v 3 in the sera of the allergic patients, as well as the presence of this minor component in the preparations used in venom immunotherapy.

Optimization of Aspergillus versicolor Culture and Aerosolization in a Murine Model of Inhalational Fungal Exposure

Aspergillus versicolor is ubiquitous in the environment and is particularly abundant in damp indoor spaces. Exposure to Aspergillus species, as well as other environmental fungi, has been linked to respiratory health outcomes, including asthma, allergy, and even local or disseminated infection. However, the pulmonary immunological mechanisms associated with repeated exposure to A. versicolor have remained relatively uncharacterized. Here, A. versicolor was cultured and desiccated on rice then placed in an acoustical generator system to achieve aerosolization. Mice were challenged with titrated doses of aerosolized conidia to examine deposition, lymphoproliferative properties, and immunotoxicological response to repeated inhalation exposures. The necessary dose to induce lymphoproliferation was identified, but not infection-like pathology. Further, it was determined that the dose was able to initiate localized immune responses. The data presented in this study demonstrate an optimized and reproducible method for delivering A. versicolor conidia to rodents via nose-only inhalation. Additionally, the feasibility of a long-term repeated exposure study was established. This experimental protocol can be used in future studies to investigate the physiological effects of repeated pulmonary exposure to fungal conidia utilizing a practical and relevant mode of delivery. In total, these data constitute an important foundation for subsequent research in the field.

Identification of a 17 kDa protein that is a potentially novel antigen of lettuce-associated respiratory allergy in farmers

BACKGROUND

We have identified and reported a novel antigen, nonprotein-specific secreted EP1-like glycoprotein (51 kDa), for lettuce-related respiratory allergy.

OBJECTIVE

We aimed to identify a novel antigen for lettuce-related respiratory allergy that is different from epidermis-specific secreted EP1-like glycoprotein.

METHODS

Immunoblotting was performed using an immunoglobulin E-specific antibody. The antigen-antibody reaction was confirmed by means of enzyme-linked immunosorbent assaying. LC-MS/MS analysis was carried out to detect a novel protein found in sera from 3 of 13 patients with lettuce-related respiratory allergy. Finally, we purified a novel protein from Escherichia coli.

RESULTS

Immunoblotting assays showed common bands of 17 kDa in the sera of 3 of 13 patients. An enzyme-linked immunosorbent assay confirmed that the patient sera reacted with lettuce latex juice. A 17 kDa protein band that showed antigenic reactivity in 3 of 13 patient sera was identified as a kirola-like protein by LC-MS/MS. In addition, although we purified this protein, we failed to show the inhibitory effect.

CONCLUSION

A 17 kDa protein that is a potentially novel antigen of lettuce-associated respiratory allergy was identified. In further studies, we will focus on purifying this novel protein to diagnose lettuce allergy.

Nasal IL-13 production identifies patients with late-phase allergic responses

BACKGROUND

There is limited knowledge on how local cytokine secretion patterns after nasal allergen challenge correlate with clinical symptoms especially with regard to the "late allergic response," which occurs in approximately 40% to 50% of patients with allergy.

OBJECTIVE

We sought to characterize the immunologic and clinical nasal responses to birch pollen allergen challenge with a special focus on the late allergic response.

METHODS

In this randomized, double-blind, placebo-controlled trial, birch pollen-allergic participants were challenged with birch pollen extract (n = 20) or placebo (n = 10) on 3 consecutive days. On days 1 and 3, nasal secretions were collected at selected time points over a 24-hour time course for the measurement of 33 inflammatory mediators. Clinical responses were determined through subjective symptom scores and objective nasal airflow measurements.

RESULTS

Provoked participants had significantly greater clinical responses and showed significant increases in tryptase and the soluble IL-33 receptor serum stimulation 2 (sST2) in nasal secretions within minutes compared with the placebo group. Eight of 20 provoked participants displayed high IL-13 levels 2 to 8 hours after allergen provocation. This group also showed significant changes in clinical parameters, with a secondary drop in nasal airflow measured by peak nasal inspiratory flow and increased symptoms of nasal obstruction, which significantly differed from IL-13 nonresponders after 6 hours.

CONCLUSIONS

IL-13 response status correlates with clinical responses and type 2 cytokine responses in the late phase after allergen provocation.

Relationship Between the Type of Allergen and Night Sweat in Allergic Children

BACKGROUND

Atopic diseases can accompany allergic sensitization. The amount of allergen is as important to know since allergen exposure affects sensitization development. Some allergic children complain of intense sweating during the first few hours of transition to sleep especially at night. This study was carried out to investigate the relationship between the type of allergen to which children are sensitized and night sweating.

METHODS

Children aged two to 18 years old with single allergic sensitization were included. A specific immunoglobulin E (IgE) skin prick test results were obtained from the medical records of the patients. Then, the patients' families were asked to evaluate the levels of sweating from 0 to 10 with the Visual Analogue Scale (VAS) questionnaire and the Sleep Disturbance Scale for Children (SDSC).

RESULTS

Sensitization to mites was more prevalent in the group of patients with night sweating (p<0.001), and pollen allergy was more prevalent in the group of patients without night sweating (p<0.001).  Conclusion: The amount of mites and wetness in bed sheets might be responsible for allergic sensitization. A change in clothes and bed sheets for those with intense sweating might ensure better sleep and reduce the severity of the atopic symptoms. Such a recommendation might provide a better clinical outcome in these patients.

Albumins represent highly cross-reactive animal allergens

Albumins from animals are highly cross-reactive allergens for patients suffering from immunoglobulin E (IgE)-mediated allergy. Approximately 20-30% of cat and dog allergic patients show IgE reactivity and mount IgE-mediated allergic reactions to cat and dog albumin. It is astonishing that allergic patients can develop specific IgE responses against animal albumins because these proteins exhibit a more than 70% sequence identity to human serum albumin (HSA) which is the most abundant protein in the blood of the human body. The sequence identity of cat albumin (Fel d 2) and dog albumin (Can f 3) and HSA are 82% and 80%, respectively. Given the high degree of sequence identity between the latter two allergens and HSA one would expect that immunological tolerance would prohibit IgE sensitization to Fel d 2 and Can f 3. Here we discuss two possibilities for how IgE sensitization to Fel d 2 and Can f 3 may develop. One possibility is the failed development of immune tolerance in albumin-allergic patients whereas the other possibility is highly selective immune tolerance to HSA but not to Fel d 2 and Can f 3. If the first assumption is correct it should be possible to detect HSA-specific T cell responses and HSA-containing immune complexes in sensitized patients. In the latter scenario few differences in the sequences of Fel d 2 and Can f 3 as compared to HSA would be responsible for the development of selective T cell and B cell responses towards Fel d 2 as well as Can f 3. However, the immunological mechanisms of albumin sensitization have not yet been investigated in detail although this will be important for the development of allergen-specific prevention and allergen-specific immunotherapy (AIT) strategies for allergy to albumin.

Comparison of Antibody Responses against Two Molecules from Ascaris lumbricoides: The Allergen Asc l 5 and the Immunomodulatory Protein Al-CPI

Immunity to Ascaris lumbricoides influences the pathogenesis of allergic diseases. Antibody responses to its proteins have been found to be associated with asthma presentation; however, helminth products that induce immunosuppression have been reported, which also raise specific antibodies. We aimed to evaluate antibody responses (IgE, IgG4 and IgG) to two A. lumbricoides molecules, Asc l 5 and Al-CPI (an anti-inflammatory Cysteine Protease Inhibitor), in an endemic population, exploring their relationships with the infection and asthma. The two molecules were produced as recombinant proteins in E. coli expression systems. Specific antibodies were detected by ELISA. Lower human IgE, but higher IgG4 and IgG antibody levels were observed for Al-CPI than for rAsc l 5. The IgE/IgG4 isotype ratio was significantly higher for Asc l 5 than for Al-CPI. In humans Al-CPI did not induce basophil activation as has been previously described for Asc l 5. In mice, Al-CPI induced fewer IgE responses, but more IgG2a antibody titers than rAsc l 5. Our results suggest that these molecules elicit different patterns of immune response to A. lumbricoides.

Identification of carboxymethyl (CM)-binding proteins derived from Lolium multiflorum pollen extract and antibody reactivity in Brazilian allergic patients

Lolium multiflorum grass is the major pollen allergen source in the southern region of Brazil, but most of its allergens remain poorly characterized. The aim of this study was to investigate antibody reactivity to L. multiflorum crude and carboxymethyl-ligand extracts in allergic patients and healthy individuals. Ion exchange carboxymethyl (CM) chromatography (CM-Sepharose) was used to isolate proteins (S2) from L. multiflorum crude extract (S1), which were assessed by SDS-PAGE. S1- and S2-specific IgE and IgG4 levels were measured by ELISA using sera from 55 atopic and 16 non-atopic subjects. Reactive polypeptide bands in S1 and S2 were detected by immunoblotting, and the most prominent bands in S2 were analyzed by mass spectrometry (MS-MS). Similar IgE and IgG4 levels were observed to both S1 (IgE median absorbance: 1.22; IgG4 median absorbance: 0.68) and S2 (IgE median absorbance: 1.26; IgG4 median absorbance: 0.85) in atopic subjects. S1 and S2 had positive correlations for IgE and IgG4 (IgE: r=0.9567; IgG4: r=0.9229; P<0.0001) levels. Homology between S1 and S2 was confirmed by IgE (84%) and IgG4 (83%) inhibition. Immunoblotting revealed that the 29-32 kDa band was recognized by 100% of atopic subjects in both S1 and S2. MS-MS analysis identified similarity profile to groups 1 and 5 grass allergens. This study revealed that carboxymethyl-ligand fraction played an important role for pollen allergy diagnosis by containing clinically relevant allergens and constituted a promising candidate for allergen-specific immunotherapy.

Environmental allergen reduction in asthma management: an overview

Asthma is a prevalent non-communicable disease that affects both children and adults. Many patients with severe, uncontrolled asthma could not achieve total control despite using anti-asthmatic drugs. There is increasing evidence that allergy to environmental allergens, including both indoor and outdoor allergens, is associated with asthma symptoms and severe asthma. Frequently reported sensitized allergens were dust mites, cockroaches, grass pollens, molds, pets, and rodents in allergic asthma patients, although the patterns of widespread allergens differed from each country. Allergen avoidance is the cornerstone of asthma management, especially in sensitized subjects. This review summarizes environmental allergen avoidance and clarifies their effects on asthma control. Despite contrasting results about the impact of allergen exposure reduction on asthma control, several studies supported the beneficial effects of reducing asthma-related symptoms or risk of exacerbations as a nondrug therapy. Identifying environmental allergens is helpful for asthma patients, and further studies on clinically effective avoidance methods are required.

Proteome of urticating setae of Ochrogaster lunifer, a processionary caterpillar of medical and veterinary importance, including primary structures of putative toxins

Ochrogaster lunifer (Lepidoptera: Notodontidae) is an Australian processionary caterpillar with detachable urticating setae that have a defensive function. These true setae induce inflammation when they contact human skin, and equine foetal loss syndrome if they are accidentally ingested by gravid horses. We used transcriptomics and proteomics to identify proteins and peptides present in and on urticating setae, which may include toxins that contribute to inflammation and/or foetal loss syndromes. This process identified 37 putative toxins, including multiple homologues of the honeybee venom peptide secapin, and proteins with similarity to odorant binding proteins, arylphorins, and the insect immune modulator Diedel. This work identifies candidate molecules that may contribute to the adverse effects of processionary caterpillar setae on human and animal health.

Corrigendum: The human milk proteome and allergy of mother and child: exploring associations with protein abundances and protein network connectivity

[This corrects the article DOI: 10.3389/fimmu.2022.977470.].

Clinical severity of LTP syndrome is associated with an expanded IgE repertoire, FDEIA, FDHIH, and LTP mono reactivity

Summary

Background. LTP allergy is often a challenge for clinicians. We evaluated a multiplex diagnostic approach with diverse cofactors to stratify LTP syndrome risk. Methods. Of the 1,831 participants screened with 'Allergy Explorer-ALEX-2', 426 had reactions to at least one LTP. Data was gathered and recorded via an electronic database. Results. Reactivity to peach Pru p 3 was found in 77% of individuals with LTP allergy. Higher levels of specific IgE and concurrent sensitization to more than 5 molecules (50% of all LTP-sensitised participants, 62% of symptomatic cases) were significantly associated with an increased risk of severe reactions (p = 0.001). Several cofactors, either alone or in combination, also influenced patients' clinical outcomes. Some cofactors increased the risk of severe reactions, such as mono reactivity to LTP in 44.6% of cases (p = 0.001), FDEIA in 10.8% of patients (p = 0.001), and FDNIH in 11.5% (p = 0.005). On the other hand, reactivity to PR10 (24.2%; p = 0.001), profilin hypersensitivity (10.3%; p = 0.001), and/or atopic dermatitis (16.7%; p = 0.001) had a mitigating effect on symptom severity. Conclusions. Clinical severity of LTP syndrome is associated with an expanded IgE repertoire in terms of the number of LTP components recognized and increased IgE levels in individual molecules. Ara h 9, Cor a 8, and Mal d 3 showed the strongest association with clinical severity. In addition, several cofactors may either exacerbate (FDEIA, FDHIH, and LTP monoreactivity) or ameliorate (atopic dermatitis and co-sensitization to profilin and/or PR10) individual patient outcomes. These factors may be utilized for the daily clinical management of LTP syndrome.

Purification, Immunological Identification, and Characterization of the Novel Silkworm Pupae Allergen Bombyx mori Lipoprotein 3 (Bomb m 6)

Allergic reactions caused by silkworm pupae greatly limit their utilization, and studies suggest that silkworm pupae proteins of 25-30 kDa may be the principal allergens. To further understand these allergens, we attempted to purify a protein of about 30 kDa by ammonium sulfate salting, pH-graded precipitation, and ion-exchange chromatography. The protein was identified by mass spectrometry and characterized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), western blot, enzyme-linked immunosorbent assays, circular dichroism, and fluorescence spectroscopy analyses. We identified the purified protein as Bombyx mori lipoprotein 3 (Bmlp3), which has high IgE reactivity and is a novel uncharacterized allergen that we named Bomb m 6 according to the WHO/IUIS Allergen Nomenclature Sub-Committee. This allergen is stable against heat, acids, bases, and digestion. In conclusion, we successfully purified and characterized a novel silkworm pupa allergen, which may inform the diagnosis and treatment of silkworm pupa allergies.

On-Chip Discovery of Allergens from the Exudate of Large Yellow Croaker (Larimichthys Crocea) Muscle Food by Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry

It is extremely crucial to establish facile, accurate, and fast methods for testing allergenic proteins (allergens) in seafood. The current study focuses on the evaluation of fish muscle exudate proteins in an effort to discover potential allergens in fish exudate for allergy tests. Large yellow croaker (Larimichthys crocea) was studied as a seafood model. Magnetic beads (MBs) modified with an IgE antibody were utilized to isolate allergens existing in the exudate sample. Immunoglobulin E (IgE) in blood is a class of antibodies that is mainly associated with allergic reactions. Potential allergens in the muscle exudate were fished by IgE-biofunctional MBs in microfluidic channels. The protein-attached MBs were isolated under a magnetic field, eluted, and collected. The collected eluent was digested and analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry to identify allergens. Eight allergens from large yellow croaker exudate were identified, i.e., parvalbumin beta, parvalbumin, protein S100, histone H4, cytochrome c, fatty acid binding protein 3 (FABP3), microsomal glutamate S-transfer 3 (MGST3), and C-C motif chemokine 21 (CCL21). The presently proposed microfluidic-magnetic-based allergen extraction protocol enables a facile and rapid test of potentials of seafood allergies, providing a solution to circumvent food safety issues, especially for allergic populations.

Allergy patient-specific IgE antibody shows significantly stability during 3 months of storage at multiple temperatures from -80 to 25°C

The detection of allergen-specific IgE antibodies is an important biomarker for the diagnosis and treatment monitoring of allergic diseases. And the pre-analytical phase is an important part of the overall quality of the laboratory. In this study, 44 patients with allergic diseases (including 23 patients with allergic rhinitis, 12 patients with allergic rhinitis and asthma, and 9 patients with allergic dermatitis) were included in the outpatient center of the Department of Allergy, the First Affiliated Hospital of Guangzhou Medical University. We mixed the serums of the above 44 patients (approximately 0.8 ml of serum volume per patient) into a large volume of serum pool (about 35 ml in total) and divided into 26 parts. And 26 serum samples were stored at 4 different temperatures for 90 days to observe the stability of sIgE antibodies to 16 allergens in serum. The results show that serum sIgE antibody titers in patients with allergic diseases show significant stability during 90 days of storage, even at room temperature. Good stability even after up to 10 freeze-thaw cycles under low temperature storage conditions.

A Cell-Free Protein Synthesis Platform to Produce a Clinically Relevant Allergen Panel

Allergens are used in the clinical diagnosis (e.g., skin tests) and treatment (e.g., immunotherapy) of allergic diseases. With growing interest in molecular allergy diagnostics and precision therapies, new tools are needed for producing allergen-based reagents. As a step to address this need, we demonstrate a cell-free protein synthesis approach for allergen production of a clinically relevant allergen panel composed of common allergens spanning a wide range of phylogenetic kingdoms. We show that allergens produced with this approach can be recognized by allergen-specific immunoglobulin E (IgE), either monoclonals or in patient sera. We also show that a cell-free expressed allergen can activate human cells such as peripheral blood basophils and CD34+ progenitor-derived mast cells in an IgE-dependent manner. We anticipate that this cell-free platform for allergen production will enable diagnostic and therapeutic technologies, providing useful tools and treatments for both the allergist and allergic patient.

Filling Analytical Gaps in Allergen Detection─Real-Time PCR for the Detection of Commercially Relevant Cephalopods and Gastropods in Food

Mollusks belong to the group of shellfish, which are considered to be among the elicitors of severe food allergies worldwide. In recent years, numerous PCR detection methods have been developed for other shellfish such as crustaceans. However, cephalopods and gastropods were not considered in the development of these shellfish detection systems. In this study, we have developed highly specific real-time PCR methods for the comprehensive detection of all commercially relevant cephalopod species and the gastropod families Helicidae, Buccinidae, and Muricidae in food matrices. In total, we cross-tested over 100 animal and plant species to show the specificity of our systems. The limit of detection (LOD12) was set at 1 pg of cephalopod and gastropod DNA or 10 ppm (mg/kg) spiked in a vegetarian food product. The robustness of the protocol was confirmed by testing multiple parameters while cooking and autoclaving of samples ensured the practical applicability of the systems.

Intra-cervical lymphatic immunotherapy for dust mite-induced allergic rhinoconjunctivitis in children: a 3-year prospective randomized controlled trial

Background

Pediatric allergic rhinoconjunctivitis has become a public concern with an increasing incidence year by year. Conventional subcutaneous immunotherapy (SCIT) has long treatment time, high cost and poor compliance. The novel immunotherapy significantly shortens the course of treatment by directly injecting allergens into cervical lymph nodes, which can perform faster clinical benefits to children.

Objective

By comparing with SCIT, this study aimed to evaluate the long-term efficacy and safety of intra-cervical lymphatic immunotherapy (ICLIT).

Methods

This is a prospective randomized controlled study. A total of 50 allergic rhinoconjunctivitis children with dust mite allergy was randomly divided into ICLIT group and SCIT group, receiving three cervical intralymphatic injections of dust mite allergen or three years of subcutaneous injection, separately. Primary outcomes included total nasal symptom scores (TNSS), total ocular symptom scores (TOSS), total symptom scores (TSS), total medication scores (TMS), and total quality of life score. Secondary outcomes included pain perception and adverse reactions during treatment. Other secondary outcome was change in Dermatophagoides pteronyssinus (Derp) and Dermatophagoides farina (Derf) -specific IgE level.

Results

Both groups had significantly decreased TNSS, TOSS, TSS, TMS, and total quality of life score after 36 months of treatment (p<0.0001). Compared with SCIT, ICLIT could rapidly improve allergic symptoms (p<0.0001). The short-term efficacy was consistent between the two groups (p=0.07), while the long-term efficacy was better in SCIT group (p<0.0001). The pain perception in ICLIT group was lower than that in SCIT group (p<0.0001). ICLIT group was safer. Specifically, the children had only 3 mild local adverse reactions without systemic adverse reactions. The SCIT group had 14 systemic adverse reactions. At last, the serum Derp and Derf-specific IgE levels in ICLIT and SCIT groups decreased 3 years later (p<0.0001).

Conclusion

ICLIT could ameliorate significantly the allergic symptoms in pediatric patients with an advantage in effectiveness and safety, besides an improved life quality including shortened period of treatment, frequency of drug use and pain perception.

Clinical trial registration

https://www.chictr.org.cn/, identifier ChiCTR1800017130.

Uterine Anaphylaxis Due to Subcutaneous Immunotherapy (SCIT) for Inhalant Allergens: A Case Series

Subcutaneous immunotherapy (SCIT), commonly known as "allergy shots," aims to achieve a clinical tolerance for allergens that cause symptoms of allergic rhinoconjunctivitis, allergic asthma, or insect sting allergies. Systemic reactions to SCIT are classified in severity from one organ system (grade 1) to anaphylaxis that potentially may have a fatal outcome (grade 5). Uterine cramps fall under grade 2, and they are rarely reported during SCIT. In this study, we report four cases of uterine anaphylaxis following SCIT for environmental allergens with symptoms such as severe lower abdominal cramping resembling menstrual cramps. Patients also experienced urticaria, angioedema, diffuse erythema, and flushing. None of the patients experienced uterine bleeding. To the best of our knowledge, this is the largest case series reporting this reaction to SCIT. We accompany this finding with a review of the literature on this rare but interesting topic.

Beneficial Effects of Astragalus membranaceus (Fisch.) Bunge Extract in Controlling Inflammatory Response and Preventing Asthma Features

Astragalus membranaceus (Fisch.) Bunge root is used as herbal medicine for its immunomodulating activities in Chinese medicine. Recently, beneficial properties of A. membranaceus on allergic diseases have been proposed. Here we investigated the role of a commercial extract of A. membranaceus, standardized to 16% polysaccharides, in regulating the immune-inflammatory response in vitro and in vivo and its therapeutic application in asthma. A. membranaceus extract inhibited prostaglandin E₂ and leukotriene C₄ production in stimulated J774 and peritoneal macrophages, respectively. The extract also reduced interlukin-1β, tumor necrosis factor-α, and nitrite production, affecting inducible nitric oxide synthase expression. In vivo experiments confirmed the anti-inflammatory properties of A. membranaceus, as evident by a reduction in zymosan-induced peritoneal cellular infiltration and pro-inflammatory mediator production. The efficacy of A. membranaceus extract in modulating the immune response was confirmed in a model of allergic airway inflammation. Extracts improve lung function by inhibiting airway hyperresponsiveness, airway remodeling, and fibrosis. Its anti-asthmatic effects were further sustained by inhibition of the sensitization process, as indicated by a reduction of ovalbumin-induced IgE levels and the mounting of a Th2 immune response. In conclusion, our data demonstrate the anti-inflammatory properties of the commercial extract of A. membranaceus and its beneficial effects on asthma feature development.

DeepAlgPro: an interpretable deep neural network model for predicting allergenic proteins

Allergies have become an emerging public health problem worldwide. The most effective way to prevent allergies is to find the causative allergen at the source and avoid re-exposure. However, most of the current computational methods used to identify allergens were based on homology or conventional machine learning methods, which were inefficient and still had room to be improved for the detection of allergens with low homology. In addition, few methods based on deep learning were reported, although deep learning has been successfully applied to several tasks in protein sequence analysis. In the present work, a deep neural network-based model, called DeepAlgPro, was proposed to identify allergens. We showed its great accuracy and applicability to large-scale forecasts by comparing it to other available tools. Additionally, we used ablation experiments to demonstrate the critical importance of the convolutional module in our model. Moreover, further analyses showed that epitope features contributed to model decision-making, thus improving the model's interpretability. Finally, we found that DeepAlgPro was capable of detecting potential new allergens. Overall, DeepAlgPro can serve as powerful software for identifying allergens.

Early inhalant allergen sensitization at component level: an analysis in atopic Dutch children

Background

Allergic rhinitis is a common respiratory disease in children and sensitization to inhalant allergens plays a significant role in its development. However, limited knowledge exists regarding sensitization profiles of inhalant allergen components in atopic children, particularly in the very young individuals. Understanding these profiles could provide insights into the early development of allergic rhinitis. The objective of this cross-sectional retrospective study was to evaluate the IgE-sensitization profiles to multiple inhalant allergen components and their clinical relevance in Dutch atopic children, with specific focus on children under the age of 4 years.

Methods

A total of 243 atopic children were included in the study and sensitization profiles were analyzed using multiplex microarray analysis (ISAC). Clinical information was obtained from records of a pediatric allergy outpatient clinic between 2011 and 2020. Specific IgE responses to inhalation allergen components from five allergen sources (grass pollen, tree pollen, house dust mite, cat and dog), were examined. The study encompassed children of different age groups and compared those with and without symptoms.

Results

The results demonstrated that sensitization to inhalant allergen components was present in 92% of the cohort. Sensitization was already evident at a young age (87%), including infancy, with a rapid increase in prevalence after 1 year of age. House dust mite emerged as the most predominant sensitizing allergen in early childhood, followed by tree pollen in later years. Sensitization patterns were similar between symptomatic and asymptomatic children, although symptomatic children exhibited higher frequencies and values. The sensitization profiles in very young children were comparable to those of children across all age groups.

Conclusion

These findings highlight the presence of sensitization to inhalant allergen components and the early onset of allergic rhinitis before the age of 4, including infancy, in Dutch atopic children. Notable allergen molecules in Dutch atopic children under the age of 4 years include Bet v 1, Fel d 1, Der f 1, Der p 1, Der p 10 and Phl p 4, with house dust mite sensitization being the most common among Dutch infants. Moreover, the prevalence of sensitization to inhalant allergens in this Dutch cohort surpassed that of general European populations, emphasizing the importance of early assessment and management of allergic rhinitis in young atopic children.

Allergic contact dermatitis in pediatric practice

BACKGROUND

Allergic contact dermatitis (ACD) is prevalent among pediatric population, adolescent and young adults. Patients with ACD experience a lot of sociopsychological and quality-of-life (QoL) difficulties. Children and their caregivers alike are vulnerable to the burden of ACD.

OBJECTIVE

We have, in this paper, provided an overview of ACD and discussed common and unusual causes of ACD.

METHODS

We performed an up-to-date literature review in the English language on "allergic contact dermatitis" via PubMed Clinical Queries, using the keywords "allergic contact dermatitis" in August 2022. The search included meta-analyses, randomized controlled trials, clinical trials, case-control studies, cohort studies, observational studies, clinical guidelines, case series, case reports, and reviews. The search was restricted to English literature and children.

RESULTS

ACD may be acute or chronic and it affects more than 20% of children and adults with significant quality-of-life impairments. ACD is manifested by varying degrees of cutaneous edema, vesiculation, and erythema. The hypersensitivity reaction is one of the most prevalent forms of immunotoxicity in humans. Localized acute ACD lesions can be managed with high-potency topical steroids; if ACD is severe or extensive, systemic corticosteroid therapy is often required to provide relief within 24 hours. In patients with more severe dermatitis, oral prednisone should be tapered over 2-3 weeks. Rapid discontinuation of corticosteroids can result in rebound dermatitis. Patch testing should be performed if treatment fails and the specific allergen or diagnosis remains unknown.

CONCLUSION

ACD is common and can be a physically, psychologically, and economically burdensome disease. Diagnosis of ACD is primarily based on history (exposure to an allergen) and physical examination (morphology and location of the eruption). Skin patch test can help determine the causative allergen. Allergen avoidance is the cornerstone of management. Topical mid- or high-potency corticosteroids are the mainstay of treatment for lesions on less than 20% of the body area. Severe cases of ACD may require treatment with systemic corticosteroids.

An Impedance-Based Immunosensor for the Detection of Ovalbumin in White Wine

Food allergies are an exceptional response of the immune system caused by the ingestion of specific foods. The main foods responsible for allergic reactions are milk, eggs, seafood, soy, peanuts, tree nuts, wheat, and their derived products. Chicken egg ovalbumin (OVA), a common allergen molecule, is often used for the clarification process of wine. Traces of OVA remain in the wine during the fining process, and they can cause significant allergic reactions in sensitive consumers. Consequently, the European Food Safety Authority (EFSA) and the American Food and Drug Administration (FDA) have shown the risks for allergic people to assume allergenic foods and food ingredients, including eggs. Commonly, OVA detection requires sophisticated and time-consuming analytical techniques. Intending to develop a faster assay, we designed a proof-of-concept non-Faradaic impedimetric immunosensor for monitoring the presence of OVA in wine. Polyclonal antibodies anti-OVA were covalently immobilised onto an 11-mercaptoundecanoic-acid (11-MUA)-modified gold surface. The developed immunosensor was able to detect OVA in diluted white wine without the need for an external probe or any pre-treatment step with a sensitivity of 0.20 µg/mL, complying with the limit established by the resolution OIV/COMEX 502-2012 for the quantification of allergens in wine.

IgE-Mediated Shellfish Allergy in Children

Shellfish, including various species of mollusks (e.g., mussels, clams, and oysters) and crustaceans (e.g., shrimp, prawn, lobster, and crab), have been a keystone of healthy dietary recommendations due to their valuable protein content. In parallel with their consumption, allergic reactions related to shellfish may be increasing. Adverse reactions to shellfish are classified into different groups: (1) Immunological reactions, including IgE and non-IgE allergic reactions; (2) non-immunological reactions, including toxic reactions and food intolerance. The IgE-mediated reactions occur within about two hours after ingestion of the shellfish and range from urticaria, angioedema, nausea, and vomiting to respiratory signs and symptoms such as bronchospasm, laryngeal oedema, and anaphylaxis. The most common allergenic proteins involved in IgE-mediated allergic reactions to shellfish include tropomyosin, arginine kinase, myosin light chain, sarcoplasmic calcium-binding protein, troponin c, and triosephosphate isomerase. Over the past decades, the knowledge gained on the identification of the molecular features of different shellfish allergens improved the diagnosis and the potential design of allergen immunotherapy for shellfish allergy. Unfortunately, immunotherapeutic studies and some diagnostic tools are still restricted in a research context and need to be validated before being implemented into clinical practice. However, they seem promising for improving management strategies for shellfish allergy. In this review, epidemiology, pathogenesis, clinical features, diagnosis, and management of shellfish allergies in children are presented. The cross-reactivity among different forms of shellfish and immunotherapeutic approaches, including unmodified allergens, hypoallergens, peptide-based, and DNA-based vaccines, are also addressed.

Exploring plant polyphenols as anti-allergic functional products to manage the growing incidence of food allergy

The active substances derived from plants have received increasing attention owing to their wide range of pharmacological applications, including anti-tumor, anti-allergic, anti-viral, and anti-oxidative activities. The allergy epidemic is a growing global public health problem that threatens human health and safety. Polyphenols from plants have significant anti-allergic effects and are an important source of anti-allergic drug research and development. Here, we describe recent advances in the anti-allergic efficacy of plant polyphenols, including their comprehensive effects on cellular or animal models. The current issues and directions for future development in this field are discussed to provide a theoretical basis for the development and utilization of these active substances as anti-allergic products.

[Characteristics of allergen component in dust mite-induced allergic rhinitis patients]

Objective:To investigate the characteristics of allergen component in dust mite（DM） -induced allergic rhinitis（AR） patients, and provide reference for the diagnosis and treatment of AR. Methods:DM-induced AR patients with or without allergic asthma（AA） who visited the Allergy Department of Tongji Hospital, Huazhong University of Science and Technology between 2021 and 2022 were enrolled. Patients'age, gender, and visual analog scale（VAS） for symptoms were recorded. sIgE and sIgG4 levels of allergen components such as Der f1, Der f2, Der p1, Der p2, Der p7, Der p10, Der p21, and Der p23 were detected using a protein chip method. The sensitization characteristics of the allergen components in the patients were observed, and the correlation between sIgE, sIgG of each component and VAS as well as the component differences between AR and AR with AA（AR&AA） were evaluated. Results:A total of 87 DM-induced AR patients were enrolled, with 42.5% of them were AR&AA, their VAS scores were significantly higher than those of AR patients（6.38±1.95 vs 5.25±1.85, P=0.009 8）. The order of sensitization rates for DM components was as follows: Der p2（82.8%）, Der f2（81.6%）, Der p1（74.7%）, Der f1（70.1%）, and Der p23（35.6%）. The order of positive rates for sIgG4 was: Der p2（21.8%）, Der f2（13.8%）, Der p21（8.0%）, and Der p7（6.9%）. There were no correlation between the sIgE, sIgG4 levels or positive numbers of components and VAS scores, but there were positive correlations between sIgE, sIgG4 concentrations of components. Compared with AR patients, AR&AA patients had higher levels of sIgE for Der p（60.5[7.2-91.1]vs 14.0[4.8-45.1], P=0.02）, Der f（49.8[15.7-81.6]vs 21.3[7.0-50.2], P=0.04）, Der p1（27.2[0.7-51.5]vs 2.6[0.2-24.9], P=0.02）, Der p2（20.0[1.4-60.6]vs 5.5[0.6-19.1], P=0.004）, and Der f2（58.9[16.0-89.2]vs 23.4[0.9-56.8], P=0.009）, and a higher proportion of AR with AA patients had sIgE levels of Der p1（70.3% vs 48.0%, P=0.038） and Der p23（27.0% vs 14.0%, P=0.039） that were ≥3 grades. Conclusion:Der p1/f1, Der p2/f3, and Der p23 are the major components of DM sensitized AR patients. Multiple component sensitization and sIgE, sIgG4 levels of each component are not correlated with the severity of AR. The sIgE levels of the Der p1/f1, Der p2/f3, and Der p23 components in AR&AA patients are higher than AR.

Sensitization trajectories to multiple allergen components in a population-based birth-cohort

BACKGROUND

The characteristics of allergic sensitization profiles can differ between populations and geographic regions, contributing differently to the association with allergic diseases. Consequently, the sensitization trajectories found in previous studies conducted in Northern Europe may not apply in Southern European countries.

OBJECTIVE

To identify trajectories of allergic sensitization profiles during childhood and evaluate the association with allergic outcomes, using data from a Portuguese birth cohort.

METHODS

A random sample from Generation XXI was screened for allergic sensitization at 10 years of age. Among 452 allergic sensitized children, 186 were tested with ImmunoCAP^™ ISAC multiplex array that detects 112 molecular components, at three follow-ups (4, 7, and 10 years old). Information on allergic outcomes (asthma, rhinitis, atopic dermatitis) was obtained at the 13-year-old follow-up. Latent class analysis (LCA) was used to identify clusters of participants with similar sensitization profiles. Then, sensitization trajectories were defined based on the most prevalent transitions between clusters over time. Logistic regression was applied to estimate the association between sensitization trajectories and allergic diseases.

RESULTS

Five trajectories were proposed: "no/few sensitizations," "early persistent house dust mites (HDM)," "early HDM and persistent/late grass pollen," "late grass pollen," and "late HDM." The "early HDM and persistent/late grass pollen" trajectory was associated with rhinitis and "early persistent HDM" with asthma and rhinitis.

CONCLUSION

Distinct sensitization trajectories pose different risks in the development of allergic diseases. These trajectories present some differences from those in Northern European countries and are important for planning adequate prevention health plans.

[Research progress and clinical application of allergen nasal provocation test]

The allergen nasal provocation testing（NPT）, in which allergens are applied directly to the nasal mucosa under standard and controlled conditions to provoke the main symptoms of allergic rhinitis（AR）, reproduces the response of the upper respiratory tract to natural exposure to allergens under controlled conditions and is the only test currently available to confirm nasal reactivity to allergens. It is invaluable in studying the mechanisms of AR and in assessing the response to novel anti-allergic treatments. The test may play an increasingly important role in clinical practice, especially in the identification of local AR, the diagnosis of occupational AR, the clarification of the composition of allergens, the assessment of the efficacy of AR treatment and the selection of candidates undergoing allergen immunotherapy. This article reviewed the application of NPT in the diagnosis of allergic and non-allergic rhinitis, and also introduces the indications, contraindications, advantages and limitations of NPT in evaluating nasal response.