Publications

Summary:

In this retrospective analysis, the sensitisation patterns were examined using the ALEX2 Allergy Xplorer with excellent sensitivity and specificity. Interestingly, age-dependent sensitization patterns were observed:

• In children up to 6 years, Ara h 1 (7/8S Globulin) was the most common sensitising allergen.

• In children at the age of 7 years and older, sensitisation to Ara h 8 (PR-10) was the most frequent.

• A growing prevalence of Bet v 1-dependent Ara h 8-sensitisation with age has been observed. The authors from this study conclude, that testing for all molecular peanut components is important. Especially seed storage proteins are associated with an increased risk of severe allergic reactions upon contact with peanuts.

doi: 10.5114/ada.2022.124741. Epub 2023 Feb 27. PMID: 36909918; PMCID: PMC9993191.

The present study is the first investigating that the ALEX2 Allergy Xplorer is a reliable and useful stand-alone tool in the bottom-up for the diagnosis of tree nut allergy in children. In 169 children, skin prick tests, extract- and molecular allergen-specific IgE antibodies were examined for clinical relevance.

In singleplex tests, rAna o 3, nCor a 9/rCor a 14, and nJug r 1/nJug r 4 were found to be important in predicting clinical reactivity to cashew/pistachio, hazelnut, and walnut, respectively. However, disadvantages of singleplex tests include high costs and excessive blood sampling in multi-sensitised patients, and a limited number of components.

Using the ALEX2 Allergy Xplorer, tree nut allergens were found to be predictors for clinical reactivity. In detail, rPis v 1/rAna o 3, rPis v 1/nPis v 2/nPis v 3/rAna o 3, nCor a 9/nCor a 11/rCor a 14, and nJug r 1/nJug r 2/nJug r 4/nJug r 6 were significant in predicting clinical reactivity to cashew, pistachio, hazelnut, and walnut, respectively. However, there was moderate variability in the cut-off levels of these components. It seems logical to use a few empirical cut-off levels for different TN components. Hence, the investigation of different cut-off values and combinations of the components with SPT, sIgE and each other revealed that at the threshold of 1.0 kAU/L, rPis v 1 and rCor a 14 optimised predicting clinical reactivity to pistachio and hazelnut with 85.3 and 89.3% accuracy, respectively. A combination of nJug r 1 and nJug r 2 positivities had highest accuracy (89.5%) in predicting clinical reactivity to walnut. Furthermore, all patients with higher concentrations of rPis v 1 (≥15.0 kUA/L), rCor a 14 (≥5 kUA/L) and nJug r 1/nJug r 2 (≥15 kUA/L) were clinically reactive to pistachio, hazelnut and walnut, respectively.

doi: 10.1016/j.alit.2021.10.001

Aytekin ES et al; Clin Exp Allergy 53(10):1041-1044, 2023; doi: 10.1111/cea.14350

Background

Molecular allergy diagnostics, such as the ALEX² test, offer a more refined approach for allergy diagnostics by reducing the need for oral food challenges and enabling the simultaneous detection of IgE reactivity to a broad panel of allergens. This study evaluated the diagnostic accuracy of ALEX² compared to conventional serological and skin tests. Therefore, a total of 123 Turkish children with peanut sensitisation were assessed.

Key findings:

• 31 (25%) children were clinically reactive to peanut, while 92 (75%) were tolerant and subsequently grouped
• Ara h 2 and Ara h 6 were detected in 83.9% and 77.4% of the clinically reactive group, but only in 15.2% and 10.9% of the tolerant group
• For Ara h 1 and Ara h 3, detection rates were 96.8% and 90.3% in the reactive group, compared to 70.7% and 37.0% in the tolerant group
• Considering 2S albumin sensitisation, IgE reactivity was 9.7% to Ara h 2 only, 3.2% to Ara h 4 only, 74.2% to both, and 12.9% to neither in the clinically reactive group
• The 12.9% not sensitised to Ara h 2 & 6, were also not sensitised to Ara h 1 & 3
• Ara h 8 was detected in 3 peanut-tolerant patients, while Ara h 9 was detected in 48.4% of the clinically reactive group & 38.0% of the tolerant group
• Comparison of AUCs showed similar diagnostic potential for peanut allergy, with no significant differences between SPT (AUC = 0.927), peanut extract sIgE (AUC = 0.854), and IgE to Ara h 1, 2, 3, and 6 (AUCs = 0.829–0.882)
• Combining diagnostic tests improved peanut sensitisation accuracy
• The combination of Ara h 2, Ara h 6 and SPT had the best accuracy (90.9%) with the highest likelihood ration (LR+; 22.2)
• While Ara h 2 and Ara h 6 showed the best accuracy for predicting clinical reactivity, peanut-allergic patients had higher IgE reactivity to Ara h 1 and Ara h 3

Conclusion:

This study confirms that IgE antibodies to Ara h 1, 2, 3, and 6 predict peanut allergy in children. The combination of SPT with sIgE to Ara h 2 and Ara h 6 achieved over 90% diagnostic accuracy, thus showing that the ALEX² test complements the SPT.

Summary:

The present publication investigates the role of the nasal microbiome in individuals with non-steroidal anti-inflammatory drugs (NSAIDs)-exacerbated respiratory disease (NERD). The study aims to shed light on the potential influence of the nasal microbiome in NERD patients without corticosteroid therapy, as the microbiome plays a vital role in respiratory health and inflammation. NERD is a condition characterized by the exacerbation of respiratory symptoms, such as asthma and rhinitis, upon the use of NSAIDs. The ALEX2 Allergy Xplorer was used to determine the IgE sensitisation profile of each patient in the blood. The research team collected nasal swabs of all patients. These swabs were then analyzed to identify and compare the composition of the nasal microbiota between the two groups (NERD patients and healthy control group). The findings of the study revealed significant differences in the nasal microbiome composition. NERD patients exhibited alterations in the abundance and diversity of nasal microbial communities, suggesting a potential dysbiosis or imbalance in their nasal microbiota. Furthermore, the study highlighted specific bacterial taxa that were significantly associated with NERD. These findings provide insights into the potential role of certain bacterial species or groups in NERD pathogenesis and may have implications for future diagnostic and therapeutic approaches.

Front Immunol. 2023 Apr 14;14:1112345. doi: 10.3389/fimmu.2023.1112345. PMID: 37122714; PMCID: PMC10140405.

Biliute G et al; Clin Transl Allergy. 14(1):e12332, 2024; doi: 10.1002/clt2.12332

Background

House dust mites (HDMs) are major triggers for respiratory allergic diseases and dermatitis. Given the global prevalence of HDM allergy and its varying sensitisation profiles, this study aimed to assess the molecular allergen sensitisation patterns in the Lithuanian population, particularly focusing on Dermatophagoides pteronyssinus (Der p), and to explore patterns of concomitant reactivity among various allergens to improve HDM allergy diagnostics. Sensitisation patterns to major (Der p 1, Der p 2, and Der p 23) and minor (Der p 5, Der p 7, and Der p 21) Der p allergen components, along with allergen components from other sources, including tropomyosins (Der p 10, Per a 7, Pen m 1, Ani s 3, Blo t 10) and arginine kinases (Pen m 2, Bla g 9, Der p 20), were evaluated using the ALEX² test. A total of 1,520 individuals, both children and adults, with suspected atopic disease were examined.

Key findings:

• 1,060 (69.74%) patients showed sensitisation to inhalant, food, or insect allergens
• Thereof, 481 individuals (45.38%) exhibited sensitisation to at least one Der p allergen component
• Within the sensitised group, 37.21% were sensitised to Der p 5, 7, or 21 in addition to major allergenic components
• Different age groups showed distinct sensitisation patterns: age-related influence
• Cross‐reactivities were seen between Der p 5 & Blo t 5 and Der p 21 & Blo t 21
• 3.40% showed sensitisation to tropomyosins, and 1.79% showed sensitisation to Der p 10
• Sensitisation to arginine kinase molecular allergens (Pen m 2, Bla g 9, Der p 20) was rare in the studied population, with only 4.53% (n = 48) of all sensitised patients demonstrating a reaction to arginine kinase

Conclusion:

This study highlights significant differences in sensitisation profiles to Der p allergens within the Lithuanian population, influenced by geographical, population-specific, and age-related factors. Understanding sensitisation patterns to major and minor HDM allergen components is crucial for improved diagnosis and management of HDM‐related allergic diseases. Additionally, the study demonstrates that understanding concomitant reactivity among allergens such as Der p 5 and Blo t 5, Der p 21 and Blo t 21, as well as tropomyosins and arginine kinases, is vital for enhancing diagnostic strategies and developing targeted interventions for individuals with allergies.

Based on Heffler et al., the present study went a step further and performed a comparison between the results of ALEX® and ImmunoCAP® ISAC for specific allergen components (most common allergens in these patients) such as: IgE against tree pollen Bet v 1, grass pollen Phl p 1 and 5, house dust mite Der p 1 and 2 and cat Fel d 1. They concluded a good correlation between ALEX® and ISAC.

doi.org/10.1186/s13601-019-0270-y

In a selected population of 105 allergic patients, skin prick test (SPT), singleplex (ImmunoCAP®) and multiplex assays (Allergy Explerer ALEX®) were compared. IgE antibodies to pollen, dust mites and food allergens were detected. Their results demonstrated a substantial agreement between ALEX® and SPT. When IgE to extracts was detected, ALEX® and ImmunoCAP® showed comparable results for inhalant and food allergens. In addition, using molecular components a higher agreement was observed for inhalant and food allergen molecules. Finally, the authors appreciated that ALEX® comprises all advantages of a multiplex test, such as an easy to learn method and a precise identification of the disease-eliciting molecules. To their opinion, ALEX® gives a boost to research in Molecular Allergy.

doi: 10.1016/j.cca.2019.02.025

Summary:

In the present study, the clinical utility of the ALEX2 multiplex test compared to the ImmunoCAP singleplex test was evaluated in patients with nut allergy. Both techniques demonstrated similar sensitivities regarding walnut, hazelnut, peanut and Pru p 3 sensitizations. Based on the results of this technical validation, the ALEX2 platform was found to be a suitable technique to diagnose patients with nut allergy, except for those suffering from allergy to almond, pistachio and sunflower seeds. This could be explained by the low sensitivity detected for the whole extracts from almond, sunflower seed and pistachio.

DOI: 10.1016/j.cca.2022.08.022

Čelakovská J et al; Mol Immunol, 2024; doi: 10.1016/j.molimm.2024.09.002

Background

Latex allergy poses a significant risk for individuals with atopic dermatitis (AD). This study aimed to evaluate the sensitisation profiles to molecular components of latex and food allergens, and to compare these findings with the patients' anamnesis regarding latex and food allergen exposures. A total of 100 AD patients were tested for specific IgE levels using ALEX².

Key findings:

• 17% of patients showed sensitisation to latex
• The most common sensitisation was to Hev b 8 (8%)
• 7% of patients exhibited pruritus, contact urticaria, and redness following latex exposure, with sIgE sensitisation to Hev b 1, 3, 5, 6.02, and/or 11
• 17% of patients sensitised to latex components also showed clinical reactions to fruits, seeds, nuts, and vegetables, and 7% of patients with latex reactions had the latex fruit syndrome
• 10% of patients had no clinical reaction to latex, but tested positive for molecular components of latex and experienced clinical symptoms after ingestion of various fruits
• All patients with a positive history of latex allergy showed IgE sensitisation to latex

Conclusion:

This study provides insight into the sensitisation to molecular components of latex in AD patients. ALEX2 confirmed latex sensitisation in nearly 17% of AD patients, with the majority testing positive IgE to Hev b 8 but without clinical reactions. The molecular components Hev b 3, 5 and 6.02 were strongly associated with clinical reactivity to latex.

In this study, specific IgE antibodies of 100 patients with atopic dermatitis to the whole ALEX2® panel were evaluated. Patients with severe AD, showed high levels of specific IgE to proteins of the NPC2 family (storage mites), lipocalin (dog), arginine kinase (moulds, cockroach, house dust mite, shrimp), uteroglobin (cat, rabbit), Mn superoxide dismutase (moulds), PR-10 protein (beech, apple, hazelnut), peritrophin-like domain (house dust mite) and rye pollen. In a subgroup of patients with bronchial asthma, high IgE values against molecular components from house dust mites, storage mites, grass pollen and moulds were observed.

doi: 10.3390/ijms22105286

Molecular diagnostic tests improve laboratory diagnostics of IgE-mediated allergies. Here, ALEX2- Allergy Explorer was used to determine the sensitisation profile towards moulds and yeast in patients suffering from atopic dermatitis. The relation between the sensitization to molecular components of moulds and yeast and the severity of atopic dermatitis, and the occurrence of bronchial asthma and allergic rhinitis was evaluated. Their results demonstrated that the sensitization to Mala s 6, Mala s 11, Sac c, Asp f 6, Cla h and Cla h 8 correlates to the severity of atopic dermatitis. The sensitization to Sac c, Alt a 6, Cla h, Cla h 8 was observed significantly more frequently in patients suffering from bronchial asthma to Mala s 6 in patients suffering from allergic rhinitis. In patients with severe form of atopic dermatitis (AD), a very high level of specific IgE was recorded to Mala s 11 (in 36%) and to Asp f 6 (in 12%)

doi: 10.3390/jof7030183

Cosme J. et al; Eur Ann Allergy Clin Immunol., 2024; doi: 10.23822/EurAnnACI.1764-1489.347

Background

Allergic rhinitis (AR) is the most prevalent chronic disease globally, affecting 16.9% to 28.5% of Europeans, with a prevalence of 26.1% in Portugal. The study aimed to evaluate the sensitisation pattern to Phleum pratense and Olea europaea pollens in Portuguese patients with seasonal AR (≥ 12 years) who tested positive for both on skin prick tests (SPT). Specific IgE to Phl p 1, 2, 5, 6, 7, 12, Ole e 1, 7, and 9 was assessed using ALEX².

Key findings:

• For Phleum pratense, patients were sensitised to Phl p 1 (85.7%), Phl p 2 (45.7%), Phl p 5 (50.3%), Phl p 6 (45.7%), Phl p 7 (10.9%), and Phl p 12 (22.9%)
• For Olea europaea, patients showed sensitisation to Ole e 1 (56.6%), Ole e 7 (1.7%), and to Ole e 9 (3.4%)
• Sensitisation to Phl p 5, 6, 12 and Ole e 1 was more frequent in inland areas
• Sensitisation to Phl p 7 was more frequent in asthmatics (17.4% vs 6.6%)
• Four sensitisation patterns were identified: 53.1% were sensitised to both Phleum and Olea; 38.3% were sensitised only to Phleum; 3.4% were sensitised only to Olea; 4% did not show any positivity to Phleum and Olea
• Immunoblotting of Olea allergic patients showed a high intensity band that may correspond to Ole e 12

Conclusion:

ALEX² revealed genuine sensitisation to both Phleum and Olea in 50% of patients, with Phl p 1, 5, and Ole e 1 being the most prevalent allergens. Molecular sensitisation profiling is essential for allergy management and for selecting the appropriate allergens for allergen-specific immunotherapy (AIT).

Summary:

This research sheds light on the complex patterns of allergy sensitisation and their implications for medical needs, highlighting the importance of understanding molecular allergens and their role in allergies. It employed a European Health Examination Survey cohort (n=1462) of Luxembourg, deep personal sIgE profiling, and an unsupervised computational method.

Among the key findings:

• 42.6% of participants reported physician-diagnosed allergies, with 44% testing positive for IgE against at least one allergen or extract.
• Sensitisation sources were primarily tree pollens (52.4%), grass pollens (51.8%), and mites (40.3%).
• The youngest group of participants (25–34 years old) represented a significant cluster (24.4%) with multi-sensitisation to respiratory sources which reflects the highest medical needs. Poly-sensitisation, especially in younger individuals, was linked to more severe symptoms and potential increased socioeconomic costs.
• The study found that participants with respiratory allergies often exhibited sensitisation to multiple molecular allergens within the same group, indicating a high likelihood of clinical reactivity, particularly evident in complex IgE patterns for grass pollen allergens like Phl p 1, 2, 5, and 6. This phenomenon of antibody responses evolving to complex patterns, known as "molecular spreading," was linked to grass pollen allergy, starting with the initiator allergen Phl p 1 and subsequently expanding to include Phl p 4, 5, and other allergens.
• Certain initiator allergens, such as Phl p 1 and Bet v 1, played central roles in the progression of atopy (genetic predisposition to allergies).
• The study's network analysis revealed a significant interconnectedness of the PR-10 allergen cluster with many other clusters. Notably, this central role was confirmed as the PR-10 allergens were found to coexist with other allergens from another cluster rather than forming a separate isolated cluster.
• The largest cluster, including a quarter of sensitised participants, was characterised not only by allergens from the PR-10 protein family but also by sensitisation to airborne signifier allergens from other clusters, such as grass pollen allergens (Phl p 1, Lol p1, Phl p 5) and house dust mite allergens (Der p 2, Der f 2, Der p 1).
• The study's strengths included a deep population-based knowledge database and an extensive IgE panel for analysing complex IgE profiles.
• The study utilised the ALEX² Allergy Xplorer, which provided an extra 200 data points compared to the Immuno Solid-phase Allergen Chip. These additional data points were instrumental in defining IgE clusters, including specific allergens like Fag s 1, Cor a 1.0103, Fra a 1/3, Der f 2, Der p 23, Der p 7, and Gly d 2.
• Importantly, the study's molecule-resolved approach ensured comparability with other research studies, enhancing the depth and precision of their analysis.

https://doi.org/10.1002/clt2.12292

Since diagnosis of food allergies can be challenging, the authors of this study aimed to assess the diagnostic value of molecular multiplex test sytstems, the ImmunoCAP ISAC and the ALEX2 Allergy Xplorer, in patients with pollen-food syndrome.

For this study, 53 patients with suspected food allergic reactions were included. The diagnosis of food allergy was based on a clear medical history, SPTs with extracts followed by multiplex IgE testing. To compare both test methods, the frequencies of 40 common allergen components present on both tests were analysed. By using the ISAC as reference, sensitivity, and specificity of the ALEX2 were calculated.

The average sensitivity was 78.2% and the average specificity 98.1%. Furthermore, they observed 83.2% sensitivity and 88% specificity of PR-10 sIgE testing with ALEX2 compared with ISAC.

For better evaluation of the diagnostic value of multiplex tests in a real-life clinical setting, they additionally correlated detected sIgE levels with SPT results and clinical symptoms. Here, positive SPT results were mostly confirmed by both test methods for Ara h 8, Cor a 1, and Mal d 1-sIgE.

Concerning clinical reactions and sIgE test results, a significant correlation was observed for Mal d 1, Cor a 1 and Gly m 4 by ALEX2. For profilin sIgE reactivity, Hev b 8 was found to be a good marker in both tests.

The authors concluded that multiplex testing is beneficial to understand patient-specific individual sensitisation profiles and to provide personalised management recommendations.

doi: 10.1111/all.15329

Eidukaite A et al; World Allergy Organ J. 4;16(10):100827, 2023; doi: 10.1016/j.waojou.2023.100827

Background

Pet allergens are among the most common inhalant allergens causing allergic diseases. In recent years, there has been an increasing trend in asthma and allergic rhinitis cases due to allergy to pets. This study determined the molecular sensitisation profile to cat and dog allergens in Lithuanian children with allergy-like symptoms. A total of 574 children (0-18 years) with suspected atopic conditions were tested with ALEX². The 433 children sensitised to at least one allergen were further analysed for sensitisation to cat (Fel d 1, Fel d 2, Fel d 4, and Fel d 7) and dog (Can f 1, Can f 2, Can f 3, Can f 4, Can f 5, and Can f 6) allergen components.

Key findings:

• A high sensitisation frequency to different inhalant allergens in Lithuanian children was observed: pollen (66.3%), dust mites (44.1%), and molds (24.3%)
• More than half of the children (n=247, 57.04%) tested positive to at least one dog or cat allergen component
• 9.71% were sensitised to dog components, 29.14% to cat components and 61.13% to components from both sources
• The major sensitisers were Fel d 1 (84.8%) and Can f 1 (59.4%)
• 5.7% patients were sensitised both to Fel d 1 + Fel d 4 and Can f 1/2 + Can f 5, indicating the high risk of severe asthma
• Monosensitisation to Fel d 1 was the dominant pattern among the children (26.3%)
• 42.9% patients were sensitised to 3 or more different mammalian protein families and 40.4% to 3 or more lipocalins

Conclusion:

This study reveals a high rate of sensitisation to inhalant allergens among Lithuanian children, with dog and/or cat allergens being particularly prevalent. Most children were polysensitised to both cat and dog allergens, though sensitisation to cat allergens was more common. In conclusion, in vitro molecular allergy diagnostics is a useful tool for accurate true sensitisation diagnosis and prognosis of disease severity.

Fernandez-Lozano C et al, Vet Dermatol., 2024; doi: 10.1111/vde.13312

Background

Although food allergies have been recognized in animals for decades, their classification into IgE-mediated, cell-mediated, or mixed mechanisms is rarely used in veterinary practice. This study reported the evaluation of a lymphocyte proliferation test (LPT) in dogs with food allergies and delayed reactions (≥6h) after oral food challenges (OFC), highlighting its suitability for diagnosis. Food allergen-specific IgE was quantified using the PAX (Pet Allergy Xplorer) test.

Key findings:

• The stimulation indices were <3.0 in 10 healthy laboratory beagles and 25 healthy pet dogs, indicating 100% specificity
• All 28 dogs with delayed food allergy showed a positive stimulation to at least one food item causing delayed flares after OFC, resulting in 100% sensitivity for LPT
• LPT identified 57 of 68 food items causing delayed flares after OFC, achieving an 84% detection rate
• PAX was negative for food-specific IgE in 18 of 28 dogs (64%), as expected for delayed food allergy
• In three dogs (11%), the PAX results overlapped with LPT, suggesting a mixed food allergy

Conclusion:

In conclusion, the LPT proved to be a valuable diagnostic tool for identifying dogs with delayed food allergies, complementing serological tests that detect food allergen-specific IgE. These allergies are likely driven by a cell-mediated immune response.

In this retrospective study, blood samples from people who spent a year wintering in Antarctica and reported increased or new allergic reactions to environmental allergens after their return, were analysed.

Due to the low sample volumes, the objective was to obtain the maximal possible scientific outcome achievable on a retrospective basis. Therefore, ALEX® Allergy Explorer was chosen as it contains a very broad variety of allergen extracts and molecular allergens.

Specific IgE measurements corresponded well to the general allergen situation in various locations. Thus, where there was no pollen exposure, the kinetics also showed a reduction in specific IgE. Five participants showed the highest specific IgE levels after returning to the "normal" world. For house dust and storage mite specific IgE, the examination revealed different kinetics. Six out of 10 had the highest specific IgE concentrations at the inner Antarctic measurement time point.

To conclude, long-term residence in Antarctica can reduce sensitisation to absent allergen sources.

doi: 10.3390/biomedicines10020448

To study the risk of subcutaneous allergen specific immunotherapy (SCIT)-induced neosensitisations, total IgE, sIgE reactivity and sIgG patterns to purifed natural allergen extract and allergen components were retrospectively measured using ALEX®. In 24% of SCIT-treated patients, they found new sIgE against allergen components of the allergen source treated by SCIT. In the SCIT-treated group, neosensitisation affected major and minor allergen components, and was accompanied by a strong induction of sIgG against major components. Patients undergoing SCIT might carry an enhanced risk of neosensitisation towards formerly unrecognized allergen components. According to anamnestic data, these neosensitisations might be of clinical relevance - supporting attempts towards personalized recombinant vaccines.

doi: 10.1038/s41598-020-63087-4

Precision medicine including personalised diagnostic and therapeutic strategies requires the depiction of the disease-eliciting allergens by demonstrating the presence of allergen-specific IgE antibodies.

In order to implement precision medicine in patients with atopic dermatitis, the present study investigated the IgE molecular profile to D.pteronissinus in patients with clinically relevant house dust mite sensitisation. Skin prick tests with mite extracts and a panel of 9 individual molecular house dust mite allergens (using ALEX2® Allergy Explorer) were used to perform atopic dermatitis endotyping. 86% of patients presented IgE reactivity to major allergens (Der p 23, Der p 2, Der p 1) and 65% to mid-tier allergens (Der p 5, Der p 7, Der p 21). Der p 23 was the most prevalent allergen recognised in this population.

To conclude, the available house dust mite molecular panel precisely identifies the large majority (>97%) of D.pteronissinus allergic subjects suffering from type-2 atopic dermatitis.

doi: 10.3390/life11121418

González-Pérez et al. confirmed the dominant role of sIgE sensitization to Der p 2 and Der p 23 (86%) and Der p 1 (74%) among an asthmatic population in Spain with moderate-to-severe symptoms. Their results also demonstrated that more than 70% of the patients were sensitized to any of the major allergens, however an inclusion of allergens such as Der p 5, Der p 7 and Der p 21 enhanced diagnosis of mite-sensitized asthmatics up to >94%.

doi: 10.1159/000510118

In the present study, storage mite sensitisation profiles were determined in two different (moderate and severe) asthma phenotypes.

Methodically, IgE Western Blotting, determination of blood eosinophils as well as serological analysis using the Allergy Explorer ALEX2 were performed.

Mite group 2 allergens were most frequently recognised. Lep d 2 (83%) was the most recognised, followed by Gly d 2 (69%) and Tyr p 2 (47%) in 133/164 asthmatic patients. The majority of storage mite sensitised individuals (99%) were simultaneously sensitised to house dust mites. In respect of group 2 allergen interactions, above 90% showed a sIgE response to Der p 2.

Actually, Lep d 2 and Gly d 2 may be speculated as potential biomarkers in milder forms of asthma presentations. However, storage mite sensitisation demands specific attention, as current diagnostic and therapeutic tools are based on Dermatophagoides allergens. Individual sensitisation patterns need to be carefully evaluated for precise diagnosis and targeted allergen-specific immunotherapy.

doi:10.3390/ijms23084297

So far, shrimp allergy has been considered to result from IgE-cross-reactivity following sensitisation to Der p 10, the tropomyosin from Dermatophagoides pteronissimus. Because tropomyosin-specific IgE was found to be a good predictor of shrimp allergy in HDM-allergic individuals, singleplex assays with shrimp tropomyosin found their way into serological routine diagnosis.

However, evidence accumulated that additional allergens cause shrimp allergy and cross-reactivity with house dust mites, such as arginine kinase (Pen m 2), myosin light chain (Pen m 3), sarcoplasmic calcium-binding protein (Pen m 4), hemocyanin, triose- phosphatase-isomerase (TPI), and troponin C (Cra c 6).

In the present study, 79 individuals who experienced allergic reactions to shrimps and displayed shrimp-specific IgE in ImmunoCAP® were analysed with the Allergy Explorer ALEX2® and immunoblotting.

The ALEX2® test revealed that 42% of the patients displayed IgE to Pen m 1 (tropomyosin, 19% exclusively), 20% to Pen m 2 (arginine kinase, 3.7% exclusively), 10% to Pen m 3 (myosin light chain, 2.5% exclusively), and 11% to Cra c 6 (troponin C).

Thus, tropomyosin represented no major allergen in this cohort. Notably, 30% of the patients recognised Pen m 4 and 16% showed exclusive IgE-reactivity with confirmed clinical relevance. Therefore, Pen m 4 was considered as important as Pen m 1 for the diagnosis of shrimp allergy in Central Europe.

All recombinant allergens together achieved a sensitivity of 68%. It is expected that the inclusion of hemocyanin and ubiquitin might enhance this value as 10% and 9% of the patients recognised the corresponding proteins of 70 and 5–7 kDa, respectively, in the immunoblot.

doi: 10.1111/all.15290

Hamilton RG et al; J Asthma 1-8, 2024; doi: 10.1080/02770903.2024.2324839

Background:

Identifying a patient’s atopic status is a key factor in the management of asthma. The qualitative Phadiatop, a multi-aeroallergen singleplex screening assay by ImmunoCAP, has been used to differentiate atopic from non-atopic asthma since 2010. The quantitative multiplex array ALEX² is emerging as a promising alternative, potentially addressing limitations such as the restricted profile of 10 aeroallergen specificities found in Phadiatop. This study aimed to evaluate the strengths and weaknesses of ALEX² in screening of asthma patients for atopic status. For this purpose, the atopic status of 42 asthmatic Amish and Hutterite children with equivocal and positive Phadiatop results was assessed by ALEX².

Key findings:

• In total, 42 asthmatic children were analysed by Phadiatop and total IgE was measured
• 22 children with negative Phadiatop (<0.1 kUA/L) and total IgE <100 kU/L were defined non-atopic and thus, excluded from ALEX² testing
• Among 3 children with a negative Phadiatop but total IgE >100 kU/L and 6 children with equivocal Phadiatop (0.1-0-2 kUA/L), 44% had detectable IgE by ALEX² to mite, tree pollen, and other allergens (not detected by Phadiatop)
• Of 11 children with positive Phadiatop (>0.2 kUA/L), all but one were positive by ALEX²
• IgEs against mold and rabbit aeroallergens corresponded well with the children’s agricultural and pet exposure history
• 3 children were sensitised to profilin, nsLTP, or PR-10 protein families

Conclusion:

ALEX² macroarray containing allergen extracts and molecules proved to be a good alternative to Phadiatop in the assessment of atopic status of asthma. Screening of asthmatics for atopy with ALEX² assay instead of Phadiatop enhanced the knowledge about the IgE asthma triggers as well as genuine versus cross-reactive allergen specificities. The combination of ALEX² testing, traditional single-plex assay and patient’s clinical history provides a better interpretation of sensitisation patterns and planning of treatment strategies.

A very interesting study of 43 patients with allergies comparing two multiplex test systems (ImmunoCAP® ISAC and ALEX®) based on allergen extracts and molecules, found a good correlation between these methods. Several advantages of ALEX® were monitored, such as the ability of measuring total IgE, the high number of 282 reagents (157 extractive allergens and 125 molecular components) compared to 112 different components (both extracts and molecular allergens) in ISAC as well as the inhibition of CCD (Cross-reactive Carbohydrate Determinants) reactivity further improves the specificity of the IgE assay.

doi: 10.1186/s40413-018-0186-3

In a cohort of North American preschool asthmatics, peanut and animal allergens were identified as major allergen sources. The dataset of this study provides detailed information on molecular diagnosis in preschool asthma. In particular, seed storage proteins (Ara h 1, 2, 3, 6), uteroglobin from cat (Fel d 1), and lipocalin from dog (Can f 1) demonstrated the strongest linkage to clinical markers of asthma severity. Allergen molecules can be biomarkers for stratification and endotyping in future prospective trials.

doi: 10.1111/all.13927

Plasma from Canadian and Austrian children/adolescents with peanut/tree nut sensitisation and a cohort of sensitised, high‐risk, pre‐school asthmatics were measured with three multiplex IgE test platforms: ALEX®, MeDALL‐chip (Mechanisms of Development of Allergy) (Thermo Fisher), and EUROLINE (EUROIMMUN). Using two regression methods, they demonstrated the ability to model allergen‐specific relationships for peanut and tree nut sIgE testing at the extract and molecular‐level, in order from highest to lowest: Ara h 2, Ara h 6, Jug r 1, Ana o 3, Ara h 1, Jug r 2, and Cor a 9.

doi: 10.1111/all.14529

In the present study, specific IgE results of 100 atopic dermatitis patients using the ALEX2 Allergy Xplorer were evaluated to perform a Cluster analysis which can help in estimating allergic reactions. For example, their results strongly point towards cross-reactivity for crustacean-allergic patients to desert locust, house cricket and stable flies.

DOI: 10.1080/09540105.2021.1978942

Summary:

The purpose of the present study was to analyse the IgE reactivity to kiwi allergens using the ALEX2 Allergy Xplorer and to evaluate the clinical reactions to kiwi in a patients cohort of atopic dermatitis patients. Therefore, the sensitivity, specificity and positive predictive value of this multiplex examination was compared with the clinical reaction to kiwi. Hundred patients suffering from atopic dermatitis were examined and 15% suffered from kiwi allergy. Regarding the results of specific IgE to molecular kiwi components, Act d 1, Act d 2 and Act d 10 gave a diagnostic sensitivity of 33%. Act d 1 and Act d 2 was found to be highly specific. Furthermore, the sensitization profile to molecular allergens of latex, banana, avocado, pollen and seeds was evaluated in patients suffering from clinical reactions to kiwi. Out of the 15 patients with clinical symptoms to kiwi, one patient reacted to Hev b 6.02 (hevein precursor) and Pers a (Avocado) and the occurrence of latex fruit syndrome was expected.

DOI: 10.1080/09540105.2022.2095985

Summary:

Since fungi may colonize and damage airways and they develop on different kinds of foods, they can have great impact on the immune system. This study aimed to evaluate the relation between sensitization to molecular components of moulds and yeast (Mala s 5, Mala s 6, Mala s 11, Sac c, Alt a 1, Alt a 6, Asp f 1, Asp f 3, Asp f 4, Asp f 6, Cla h 8, Pen ch) and the occurrence of food hypersensitivity reactions in 100 atopic dermatitis patients. The sensitization profiles demonstrated that patients with reactions to hazelnuts, walnuts, peanuts, fish and egg had higher levels of sIgE to Asp f 3, Cla h 8, Alt a 6, Alt a 1, Mala s 6 and Asp f 6.

DOI: 10.1080/09540105.2022.2074968

This is the first study using a multiplex technology to investigate IgE sensitizations to parvalbumins from 10 fish species, along with fish extracts from raw and heated fish material. Serum samples from 263 clinically well-defined fish allergic patients from a multinational cohort were analyzed regarding their sensitization patterns in a research version of the ALEX2 Allergy Xplorer.

Main findings:

• Up to 90% of the patients showed no IgE to parvalbumins and extracts from ray.

• Up to 21% tested negative for some bony fish species.

• Up to 38% were negative to cod parvalbumins, which is the most commonly used molecule in fish allergy diagnosis. Thus, this fish allergy marker may not be sufficient for accurate fish-allergy diagnosis.

• 17% tested negative to parvalbumins, but positive to the respective fish extracts, underlining the requirement for extracts for accurate diagnosis.

• Of the species analyzed, negativity to mackerel emerged as the best predictive marker of negativity to additional bony fish, such as herring or swordfish.

To conclude, this study demonstrates the need for extracts from both raw and heated fish and the parvalbumins from several evolutionary distant species for next-generation fish allergy diagnosis.

doi: 10.1016/j.jaip.2022.08.019

Kalyniuk V et al; Frontiers in Allergy Vol. 5, 2024; doi: 10.3389/falgy.2024.1438393

Background

Sensitisation to fungi is a significant factor in allergic rhinitis and asthma. Moreover, it has been shown that a large proportion of severe asthmatics are sensitised to fungal allergens such as Alternaria and Aspergillus. This study investigated the sensitisation profiles of patients hypersensitive to fungal allergens in the Ukrainian population, examine their co-sensitisation to other allergens, and explore the relationships between different allergens in provoking hypersensitivity. Children and adults (n= 3,349; 77.84% children vs. 22.16% adults) sensitive to fungal components were tested via ALEX² in 17 regions of Ukraine. Eligible participants had a history of allergic rhinitis, chronic urticaria, allergic dermatitis, or asthma along with sensitisation to fungal allergens.

Key findings:

• 79.30% were sensitive to Alt a 1 and 62.09 % showed Alt a 1 mono-sensitisation
• Fungi-polysensitised patients were found to have unique allergological profiles, with 84.77% reacting to two or more allergens from various groups
• The immune response to Alt a 1 may trigger sensitisation to various other common allergens, increasing the likelihood of sensitivity to grasses (primarily to Phl p 2), ragweed (Amb a 1), pectate lyase (Cry j 1), and the cat allergen Fel d 1
• Fungi-polysensitised individuals were often sensitised to cross-reactive molecules, like lipocalins (Fel d 4 and Can f 6)
• Ambrosia extract (Amb a) played a significant role in ragweed pollen sensitisation, while Phl p 2 might be important in grass sensitivity in patients with Alternaria allergy

Conclusion:

The study highlighted the participants' unique allergenic profiles, which often included multiple allergens from various sources. These findings underscore the importance of considering fungal allergens within the broader scope of allergic diseases, particularly due to their potential to enhance responses to other non-fungal allergens. In conclusion, this study emphasizes the importance of in-vitro multiplex allergy test such ALEX, which allows measurements of specific IgE against a large number of allergen extracts and molecular allergens, in patients with sensitisation to fungi.

Kazancioglu A et al; Allergy Asthma Proc 45:000-000, 2024; DOI:10.2500/aap.2024.45.230075

Background

Lipid Transfer Proteins (LTPs) are the most common cause of food-induced allergy and the primary cause of food-induced anaphylaxis in Mediterranean region. This cross-sectional study investigated the sensitization patterns of LTPs in eastern Mediterranean children and their clinical significance. A total of 496 children were evaluated for multiple sensitisations by ALEX² testing. Of these, 105 children (21%) with at least one LTP sensitisation were included in the study. Clinical reactivity was evaluated based on IgE-mediated symptoms (oral allergy syndrome, systemic reactions, and anaphylaxis) after consuming LTP-containing foods.

Key findings:

• All children included tested positive for at least one food-related LTP
• 56% of the food LTPs-sensitive children were also sensitive to pollen LTPs
• 56% of patients experienced clinical reactivity to food-related LTPs, 43% systemic reactions, 18% anaphylaxis, and 11% oral allergy syndrome
• The most common sensitisations were Pru p 3 (74%) and Cor a 8 (66%)
• Significant correlations were observed in the heatmap between the LTP allergen molecules; the lowest correlation was found for Par j 2 and Tri a 14
• Clinical reactivity correlated with increased age and number of LTP molecule positivity

Conclusion:

In conclusion, 21% of children with multiple sensitisations were sensitised to LTP. Clinical reactivity was common, with associations found between increasing age and increasing LTP molecule positivity.

Knyziak-Mędrzycka I et al; J Clin Med 13(10):2992, 2024; doi: 10.3390/jcm13102992

Background:

Coeliac disease (CD) is the most common gluten-induced food intolerance and often co-occurs with autoimmune conditions or genetic syndromes. In this study, 108 pediatric patients with CD were tested with ALEX² to investigate the co-existence of CD and IgE-mediated allergies.

Key findings:

• 49.1% (53/108) of patients showed sensitisation to allergen extracts or molecules
• Most children, 41.5% (22/53), showed simultaneous sensitivity to food and inhalant allergens
• 38.8% (48/108) showed sensitisation to inhalant allergens with Phl p 1, Lol p 1, and Bet v 1 being the most common aeroallergens
• 26.8% (29/108) showed sIgE against food allergens and the most common were Cor a 1, Mal d 1, and Ara h 8
• Patients were not sensitised to cereal allergens containing gluten
• Spearman’s rank correlation analysis showed a significant relationship between increasing age and sensitisation to inhalant allergens (>0.3 kUA/L), not however to food allergens (<0.3 kUA/L)
• Mainly symptoms of inhalant allergy, such as hay fever, conjunctivitis and bronchial asthma, were observed in sensitised patients

Conclusion:

This study demonstrates that children with CD experience simultaneous IgE sensitisation to both food and inhalant allergens. Hence, greater emphasis should be placed on diagnosing IgE-mediated allergies in children with CD, ultimately leading to improved patient care.

Knyziak-Mędrzycka I et al; Int J Mol Sci. 25(2):825, 2024; doi: 10.3390/ijms25020825

Background

Food allergies are becoming more prevalent. Environmental factors play a significant role in allergy development, leading to diverse sensitisation patterns influenced by geographic regions, climate, dietary habits, and/or food preparation methods. The aim of this study was to conduct an in-depth evaluation of paediatric sensitisation to food allergens, with a specific emphasis on the eight major food allergens (the “Big 8”): cow milk, eggs, wheat, soybeans, fish, crustacean shellfish, tree nuts, and peanuts. To achieve this, the prevalence and serum levels of sIgE from 3,715 children and adolescents across Poland were analysed via ALEX, providing a comprehensive review of IgE sensitisation profiles based on both molecular and extract analyses of food allergens.

Key findings:

• 572 results were obtained with ALEX, and 3,143 results with ALEX2
• The final analysis included the sIgE results obtained with 95 food extracts and 77 food allergen molecules
• The highest rates of sIgE to food allergen extracts were to peanuts (29.20%), hazelnuts (28.20%), and apple (23.60%)
• The highest rates of sIgE to allergenic molecules were to PR-10 family (Cor a 1.0401 (23.77%), Mal d 1 (22.37%), Ara h 8 (16.93%)), and globulin 7/8S (Ara h 1 (15.59%)
• The lowest rates of sIgE to extracts were to strawberry (0.40%), oregano (0.30%), and thornback ray (0.16%)
• The lowest rates of sIgE to allergenic molecules were to Mal d 2 (0.27%) (TLP), Ani s 1 (0.30%) (Kunitz-type serine protease inhibitor), and Che a 1 (0.43%) (Ole e 1 family)
• The sensitisation rates to storage proteins decreased significantly with age, while the sensitisation rates to PR-10 family proteins increased significantly with age

Conclusion:

The multiplex ALEX® test showed unique molecular sensitisation profiles to major food allergens in Polish children, differing significantly from sensitisation profiles reported in other countries. Peanut, hazel, and apple consistently ranked among the top allergens, regardless of whether extracts or molecules were tested. Furthermore, serum sIgE analysis across all regions of Poland revealed an age-dependent variation in the molecular sensitisation profiles to food allergens.

Summary:

This article presents a case of a patient diagnosed with food allergy manifesting as atopic dermatitis and anaphylaxis, which evolved into childhood asthma. Diagnosis was based on the evaluation of IgE-reactivity profiles and allergen challenge. The described case shows a typical route of an allergy march from food allergy (cow’s milk, egg) manifested as atopic dermatitis to inhalation allergy (birch, timothy grass, Alternaria alternata) and asthma. The reported case presented several risk factors for the classic atopic march: atopic dermatitis in infancy, atopy in family, male gender and primary sensitization to many food allergens. The use of the ALEX2 Allergy Xplorer allows to monitor IgE sensitizations, predict the risk of anaphylaxis and assist in making decisions about dietary treatment and early allergen immunotherapy.

DOI: 10.2147/JAA.S372928

Background:

Allergic rhinoconjunctivitis affects 20% of the general population. The use of native allergen extracts decreases diagnostic specificity of pollen allergy due to CCDs (Cross-reactive carbohydrate determinants) and panallergens (profilins and polcalcins) which can hamper or confound test results. Thus, allergen extracts bear the significant risk of misdiagnosis. The aim of the present study is to determine the prevalence of multiple pollen sensitisations and cross-reactivity and to evaluate the sensitivity and specificity of molecular allergy diagnostics. This study investigated the prevalence of sensitisation to seasonal pollen extracts, cross-reactive carbohydrate determinants (CCDs), profilins, and polcalcins in a group of 2948 patients. The patients were screened for specific immunoglobulin E to ash, birch, mugwort, ragweed, and timothy grass pollen extracts. The patients were grouped based on the number of positive tests (ranging from 1 to 5), and a subset of 742 patients was used to determine the sensitivity and specificity of molecular allergy diagnosis (MAD) using commercially available test methods (ALEX2 Allergy Xplorer and ImmunoCAP).

Key findings:

Prevalence of Sensitisation:

• Remarkably, the correlation of sIgE extract and skin prick test results demonstrated that sIgE positive/prick negative patients were frequently observed for pollen allergens. 13.3% of the positive extract determinations had negative corresponding prick test results.
• 55.2% of the patients were positive to at least one of the five pollen allergens investigated
• 34.0% of the patients were positive to multiple pollen allergens
• 18.5% of pollen-sensitised patients had sensitisation to CCDs or panallergens (profilins or polcalcins).

Specific Sensitisation Rates:

• Sensitisation to CCDs was observed in 8.7% of pollen-sensitised patients
• Sensitisation to profilins was observed in 10.9% of pollen-sensitised patients
• Sensitisation to polcalcins was observed in 2.9% of pollen-sensitised patients

Molecular Allergy Diagnosis (MAD):

• The study used MAD with specific allergen components (Fra/Ole e 1, Bet v 1, Phl p 1, Art v 1, and Amb a 1).
• The sensitivity of MAD was high, ranging from 92% to 100% using ALEX2.
• Specificity was 100%.

Conclusions:

Cross-reactivity, particularly with CCDs, profilins, and polcalcins, poses a risk of misdiagnosis in about one-fifth of pollen-sensitised patients. Despite cross-reactivity challenges, MAD using specific allergen components was found to be sensitive and specific. In summary, the study highlights the importance of considering molecular components in allergy diagnosis to enhance specificity and reduce the risk of misdiagnosis in patients with pollen allergies.

Another study compared allergy tests such as singleplex assay ImmunoCAP® (detecting Der p 1, 2, 10 and 23), the multiplex assay ImmunoCAP® ISAC (detecting Der p 1, 2 and 10) and Allergy Explorer (ALEX®) versions 1 and 2 (detecting Der p 1, 2, 5, 7, 10, 11, 20, 21 and 23). In general, sensitivity of molecular tests was lower compared to singleplex extract-based testing. However, sensitivity increased the more HDM allergen molecules were included in the test. Therefore, sensitivity of ALEX2® was higher compared to all other molecular assays. A clear correlation according to sensitivity between molecular test systems with HDM sIgE levels was observed implicating that higher sIgE levels lead to better sensitivity of molecular testing. Der p 1, 2 and 23 were confirmed to be major allergens. Moreover, Der p 23 is the third major HDM allergen and therefore essential to include in molecular test systems. Importantly, ALEX2® performed statistically equal to extract-based diagnosis in patients with allergen-specific IgE levels higher that 1.0 kU/L with a sensitivity of 97.2%.

doi: 10.1111/all.14271

This case study describes a young patient with poppy seed allergy. Hazelnut allergy was found to co-occur in this patient. However, the primary responsible allergen was considered to be poppy seed.

doi: 10.18176/jiaci.0493

Short summary: In this study, a mathematical model for predicting the probability of asthma control based on the FeNO dynamics after 3 months of treatment, the number of cat allergens to which sensitisation is detected and the duration of exposure to a domestic cat after molecular allergy testing was developed.

Summary: The aim of this study was to develop a model for predicting asthma control status in school-aged children, who are sensitised to cat allergens. In this retrospective study, 302 patients were included. Inclusion criteria involved diagnosis of bronchial asthma, age 6-17 years and sensitisation to at least one of the following cat allergens Fel d 1, Fel d 2, Fel d 4, Fel d 7. Patients were selected upon careful history taking, spirometry, skin-prick test with Fel d 1 standardised extract (5,000 BAU / mL), measurement of total IgE and fractional exhaled nitric oxide (FeNO) before and after 3 months of treatment.

To obtain a comprehensive sensitisation profile, serum samples were analysed using the ALEX² test. The following sensitisation prevalences were measured:

• Fel d 1 in 291 (96.36%) children

• Fel d 2 in 18 (5.96%) children

• Fel d 4 in 59 (19.54%) children

• Fel d 7 in 75 (24.83%) children

Combined sensitisations were also observed:

• Fel d 1, Fel d 7 in 32 (10.60%) patients

• Fel d 1, Fel d 4 in 22 (7.28%) patients

• Fel d 1, Fel d 4, Fel d 7 in 22 (7.28%) patients

• Fel d 1, Fel d 2, Fel d 4, Fel d 7 in 12 (3.97%) patients

To evaluate the correlation between controlled asthma and sensitisation to cat allergens, the Searman’s rank correlation coefficient was calculated. A correlation was found between the presence of asthma control and the number of cat allergens to which the child is sensitised, which emphasises the importance of multiple sensitisations. Regarding the structure of sensitisation, a correlation was found between the presence of asthma control and sensitisation to Fel d 4 and Fel d 7. According to the Consensus document on dog and cat allergy, sensitisation to two or more allergens is associated with more severe respiratory symptoms and is a marker of severe asthma.

doi: 10.36740/WLek202206110

Summary:

In the present study, different in-vitro allergy tests were carried out using serum collected from a patient with red meat allergy. After being bitten by a tick, the patient has experienced anaphylactic reactions several times after eating red meat. The ALEX2 Allergy Xplorer demonstrated a very high concentration of total IgE (tIgG: 2602kU/L). IgE antibody levels specific for inhalative-, food and insect venom allergens were quite low. However, positive results were obtained for all mammalian meat allergens, but no IgE antibodies to poultry meat allergens were found. The ImmunoCAP confirmed the very high IgE concentration. Furthermore, inhibition experiments were performed with ImmunoCAPs. The level of anti α-Gal IgE decreased after blocking CAPs with various mammalian meat allergens. In contrast, blocking with poultry allergens did not affect the concentration of anti α-Gal IgE.

Life 2023, 13, 699. https://doi.org/10.3390/life13030699

To investigate the molecular sensitisation profile of mite allergic patients in a region with high environmental house dust and storage mite occurrence, a specific molecular allergen panel using the Allergy Explorer ALEX2 was correlated with clinical parameters.

All subjects with a positive skin prick test exhibited a positive response to one of the tested molecular allergens. 66% of the cohort recognised Der p 1, 78% Der p 2 and 86% Der p 23. The great advantage of the ALEX2 test was the additional evaluation of IgE responses to mid-tier and minor house dust mite allergens. Der p 5 revealed IgE-reactivity in 44%, Der p 7 in 36%, Der p 20 in 10% and Der p 21 in 40%. Der p 7 levels were higher among rhinitis patients. In contrast, the atopic dermatitis relative risk was increased in patients sensitised to Der f 2, Der p 2, and Der p 23. Sensitisation to Der p 10 decreases the risk to have atopic dermatitis.

The use of multiple molecular panels allows the improvement of patient management and to evaluate the risk for atopic dermatitis or other conditions like asthma or rhinitis.

doi: 10.1159/000523869

Short summary:

This study is the first to evaluate potential differences in IgE sensitisation profiles of cockroach-sensitised patients with perennial respiratory allergy symptoms from two different geographic areas: coastal China (Hong Kong, HK) and central Europe (Austria). Molecular profiling using the ALEX² Allergy Xplorer identified differences between cockroach-sensitised allergic patients from HK and Austria in terms of primary sensitisers and molecular IgE reactivity patterns. Tropomyosin from American cockroach (Per a 7) was shown to be significantly associated with asthma symptoms and might be suitable as a biomarker for more severe respiratory allergy symptoms.

Summary:

In addition to skin prick testing and/or IgE reactivity with cockroach extract, using the ELISA-based multiplex allergy test ALEX² comprising a broad panel of cockroach allergens, the aim was to assess the patients’ molecular IgE reactivity patterns and to determine the primary sensitising allergen sources and to differentiate between co- and cross-sensitisations in the studied cohorts. Molecular IgE reactivity profiles were analysed via multiplex assay for sensitisation to allergens and extracts from cockroach, house dust mite, shellfish, and 3 additional insect species. In the HK group, genuine sensitisation to cockroach was found in 45%, but none of the patients in the Austrian cohort was truly sensitised to that allergen source, thus cockroach is not a relevant primary sensitising allergen source in Austria. Most patients from HK were cross-sensitised to other insects and/or shellfish, presumably by broad reactivity to tropomyosin and arginine kinase. About half of the Austrian subjects lacked IgE to these pan-allergens, indicating co- but not cross-sensitisation to insects and/or shellfish. Regarding IgE recognition frequencies, arginine kinases (64% HK, 10% Austria) and tropomyosins (42% HK, 15% Austria) were most frequently recognised; Bla g 4 (lipocalin) was detected in HK patients only (42%). IgE sensitisation to Per a 7 was significantly higher in patients with asthma than patients without asthma. Sera from HDM-sensitised subjects from HK showed a higher proportion of sensitisation to minor mite allergens.

doi: 10.1016/j.jacig.2022.04.003

Summary:

In the present article, research on the verification and validation of the ALEX2 Allergy Xplorer in relation to the ImmunoCAP ISAC test was performed. The results obtained with the two test systems were comparable. However, the ALEX2 test comprised important features, such as unique allergen molecules and extracts and an automatic inhibition of CCD-specific IgE antibodies. Based on the determination of dominant sensitizing molecules - indications for AIT, the risk of anaphylaxis and further treatment tactics can be established.

DOI: 10.51620/0869-2084-2021-66-8-480-484

Nösslinger H et al; Diagnostics 14(10):976, 2024; DOI: 10.3390/diagnostics14100976

Background:

This study compared the performance of ImmunoCAP ISAC E112i (ISAC), which includes 112 allergen components, and Allergy Xplorer 2 (ALEX²) including 295 allergens (178 components and 117 extracts) through qualitative, semi-quantitative, and quantitative analyses of IgE antibody to all comparable allergen components in sera from 216 children and adults from South Tyrol, Italy with suspected allergies.

Key findings:

• ALEX² detected positive allergen components in 81.6% of cases and ISAC in 76.5% of cases
• MUXF3 (= CCD marker in ISAC) was positive in 24.1% (52/216) of all cases
• ALEX² CCD inhibitor reduced CCD-positive cases by 88.5% (46/52) compared to ISAC
• Overall good agreement between ALEX² and ISAC (based on sensitisation values between 0.3–14.9 ISU or kUA/L)
• The presence of allergen extracts in ALEX2 resulted in the detection of more sensitisations than ISAC

Conculsion:

The allergen extracts in ALEX² can aid the detection of more sensitisations than the corresponding allergen components alone but cannot replace them. Furthermore, ALEX² shows fewer false positives than ISAC due to CCDs blockage. Finally, ALEX² may be better suited to detect sensitisation at <15 ISU or kUA/L.

Olivry T et al, Vet Dermatol, 2024; doi: 10.1111/vde.13295

Background

In dogs, total IgE serum concentrations are much higher than in humans and do not predict allergic status. Both Toxocara canis (Tc) infestations and cross-reactivity with Dermatophagoides farinae (Df) have been shown to elevate total IgE levels and Df-specific IgE in dogs. This study aimed to identify cross-reactive allergens between Tc and Df, utilizing sera from 73 dogs suspected of Df allergy. For this purpose, PAX (Pet Allergy Xplorer) and ELISA inhibition assays were performed with Tc extracts and recombinant Tc tropomyosin.

Key findings:

• ELISA and PAX inhibitions showed mutual yet variable cross-reactivity between the Tc excretory–secretory extract, purified Der f 15, and purified Zen-1
• Cross-reactivity likely involves glycans, as no inhibition occurred between the Tc extract and recombinant Der f 15 without its O-glycans
• Heterogeneous cross-reactivity was observed between the somatic Tc extract and Der p 11 (paramyosin), and between recombinant Toxo c 3 and Der p 10 (tropomyosin)
• Cross-reactivity among tropomyosins and paramyosins likely involves peptidic epitopes, as these recombinant allergens are not glycosylated

Conclusion:

This study revealed a complex and variable cross-reactivity between Toxocara canis and Dermatophagoides farinae. It involves shared glycanic epitopes on Der f 15 and Zen-1, as well as peptidic epitopes on tropomyosins and paramyosins, though additional cross-reactive allergens may also exist. The PAX test proved to be useful and confirmed the detection rates reported in previous studies.

Fernandez-Lozano C et al, Vet Dermatol., 2024; doi: 10.1111/vde.13312

Background

Allergen immunotherapy (AIT) is the only treatment that can induce long-term tolerance in allergic humans and animals, but its efficacy and safety are often limited. Recently, virus-like particles (VLPs) have emerged as a promising alternative for AIT, offering enhanced immune responses and potential improvements in treatment outcomes. This study aimed to investigate the development of allergen-blocking IgG in dogs injected either intradermally or subcutaneously with Der f 2-carrying enveloped plant-based bioparticles (eBPs). Allergen-specific IgG serum levels were measured using ELISA. The allergen-blocking potential of postvaccination IgG was evaluated through PAX (Pet Allergy Xplorer) and basophil mediator release inhibition assays.

Key findings:

• The amount of Der f 2 eBPs needed to induce basophil activation was 1000-fold higher than that of the soluble natural allergen
• Both immunisation groups showed no adverse events and induced Der f 2-specific IgG, which was first detected two weeks after injection (Day 14) and peaked on Day 41
• Vaccine-induced Der f 2- IgG inhibited IgE binding to Der f 2 in the PAX, with a 35–40% inhibition at 2 weeks and 70–80% inhibition within one month (Day 41)
• Basophil mediator release inhibition reached 75% on Days 28 and 41 for both groups
• Inhibition of PAX and mediator release correlated significantly with Der f 2 IgG levels

Conclusion:

This study demonstrated the safety and efficacy of eBPs in inducing neutralising allergen-specific IgG, suggesting their potential as a viable option for AIT in animals and humans. The allergy-preventing benefit potential of eBPs in patients awaits the performance of clinical trials.

A new in vitro multiplex allergen assay (ALEX) which allows simultaneous measurement of specific IgE against the whole allergen extract as well as its components were used. The data showed that in Brazil the inclusion of the molecular components Blo t 5 and/or Blo t 21 major allergens and Blo t 2 can increase the sensitivity and specificity of the assay for the diagnosis of allergy to B. tropicalis. Furthermore, monosensitisation to Blo t 2 was found in some individuals. Regarding the sensitization profile of individuals sensitized to D. pteronyssinus, they demonstrated that molecular components Der p23 and Der p 7, in addition to Der p 1 and Der p 2 are essential for an accurate diagnosis.

doi.org/10.1002/clt2.12004

The aim of the present study was to analyze the performance of two different multiplex allergy test systems, ImmunoCAP ISAC® and ALEX2® Allergy Explorer using serum samples of 49 patients preselected based on positive ImmunoCAP ISAC® results. A good overall agreement (94%) and positive agreement percentage values between ISAC and ALEX2® has been observed. 59% of the qualitative discrepancies were related to weak positive results. Remarkably, the overall agreement of dichotomous results (negative, positive) was found to be identical (94.3%). However, the CCD inhibition step to block CCD-specific IgE antibodies used in the ALEX2® test revealed to be innovative and essential to obtain higher clinical specificity. Anti-CCD antibodies are reported up to 30%. Interestingly, the patient with the highest reactivity against MUXF3 (CCD) on ISAC (8.5 ISU) revealed, besides two double positive results for wasp venom (Pol d 5 and Ves v 5), 7 ISAC+/ALEX− results all of which were native proteins of plant origin and/or plant food related allergens (Cry j 1, Cup a 1, Cyn d 1, Gly m 6, Jug r 2, Sal k 1, Tri a aA_TI). Here false positive results were generated using the ISAC test.

ALEX2® was able to score plus points with the following aspects:

measurement of total IgE

absorption of sIgE against CCDs

more comprehensive allergen panel

inclusion of minor allergen components enhances clinical value

Conclusions: The method comparison between ISAC and ALEX2 multiplex tests showed a high concordance for those allergen components present on both platforms.

doi: 10.1515/cclm-2022-0191

In this study setup, three different allergy test systems - the Allergy Explorer ALEX2®, ISAC112® and ImmunoCAP® were compared according their technical performance and diagnostic capacity for the diagnosis of various allergies.

ALEX2® showed improved diagnostic capacity for Alternaria and apple allergy compared with ISAC112®, due to the better performance of Alt a 1 and the inclusion of Mal d 3, respectively. It is important to consider that in terms of CRD, extensively wide panels of allergens allow the inclusion of clinically relevant allergens such as Der p 23, absent in ISAC112®.

ALEX2® performed well in technical validation assays by measuring repeatability and inter-assay, inter-batch and inter-lab reproducibility.

doi: 10.1016/j.anai.2021.11.019

Nowadays, honey bee venom (HBV) allergy is treated by allergen immunotherapy (AIT) whose efficacy is low. Api m 10 was identified as a major allergen in HBV allergy, however the quantity of Api m 10 in the venom is of low abundance (approx. 1%). This may explain a potential link between underrepresentation in several therapeutic HBV preparations and treatment failure in dominantly Api m 10 sensitised HBV-allergic patients. In theory, this lack couled be compensated by spiking therapeutic HBV preparations with rApi m 10. However, Api m 10 is easily degraded. Therefore, alternative strategies need to be developed. To characterize the IgE response to Api m 10 in detail, linear IgE epitopes recognized by patients allergic to HBV were investigated. Synthetic peptides spanning the whole amino acid sequence of Api m 10 were coupled to macroarrays (Macro Array Diagnostics). Interestingly, one peptide, P54 (Api m 10160‐174; amino acid sequence: ADSDVTTLPTLIGKN), was recognized by 100% of the Api m 10‐positive sera and hence represents the dominant linear IgE epitope of Api m 10. A short immunodominant peptide is easier to produce, can be included in therapeutic preparations and thus may have relevant advantages over the use of full‐length rApi m 10.

doi: 10.1111/all.14187

Reznik Y. V. et al; Regul. Mech. Biosyst. 14(4), 2023; doi: 10.15421/022391

Background

Fungi are ubiquitous microorganisms found in both indoor and outdoor environments. They play significant roles in ecology and agriculture but also pose health risks, particularly through fungal allergies, which are among the most common health issues globally. The primary focus of this study was to assess the sensitivity to fungal allergens in individuals from the Vinnytsya region. A total of 87 individuals, aged 1 to 66, were analysed for IgE-mediated genuine sensitisation to fungal allergens, including Alternaria (Alt a 1, Alt a 6), Cladosporium (Cla h, Cla h 8), Aspergillus (Asp f 1, Asp f 3, Asp f 4, Asp f 6), Penicillium (Pen ch), Malassezia (Mala s 11, Mala s 5, Mala s 6), and Saccharomyces (Sac c), using the ALEX² test.

Key findings:

• Sensitivity to fungal allergens was identified in 20 patients, representing 23.0% of those tested
• The highest level of sensitivity was observed to Alternaria fungus (in 75% of tested patients): 14 (93.3%) patients were sensitive to Alt a 1, one of whom was also sensitive to Alt a 6; o One patient was sensitive only to Alt a 6
• Sensitivity to Aspergillus and Malassezia was the second highest, with 6 patients (30%) of sensitised individuals, reacting to these two fungal allergens: One patient was sensitised to Asp f 4; Two patients were sensitised to Mala s 6; Patients sensitised to Aspergillus were also co-sensitised to Alternaria, while those sensitised to Malassezia were co-sensitised to Alternaria, Aspergillus, and Cladosporium
• Two patients were sensitised to Cladosporium
• One patient was sensitised to Penicillium but no other fungal allergen

Conclusion:

This study revealed that Alternaria was the leading cause of sensitisation in the tested population of the Vinnytsya region, followed by Aspergillus allergens, which are clinically known to trigger both allergic and infectious reactions. Although Cladosporium typically has the highest spore counts in the air, it is characterised by low allergenicity. Elevated levels of specific and total IgE can act as predictive markers for potential fungal allergies, highlighting their significance in diagnosis and prevention. In this regard, the ALEX² test is particularly valuable, as it enables simultaneous measurement of total and specific IgE for a wide range of fungal allergens, aiding in the distinction between genuine sensitisation to fungal allergens and cross-reactive allergens.

Rodinkova V et al; World Allergy Organ J. 17(5):100908, 2024; doi: 10.1016/j.waojou.2024.100908

Background

Fungi are able to trigger respiratory tract allergic diseases, yet there is a lack of sufficient data regarding individual sensitisation to fungal allergens. This study focused on analysing the epidemiological patterns of age-related, individual, and regional sensitisation to fungal allergens within the Ukrainian population. A total of 20,033 individuals, both children and adults, with a history of allergic rhinitis, atopic dermatitis and/or asthma were tested with ALEX². A complex of programs in the Python language was developed and Bayesian network analysis was applied to determine the sensitivity combinations in individual patients to various fungal components.

Key findings:

• 16.71% individuals showed sensitivity to at least one fungal allergen
• Sensitivity to Alt a 1, either alone or in combination with other allergens, was observed in 79.39%, making it the most common sensitisation
• 62.17% individuals showed mono-sensitisation to Alt a 1
• Mono-sensitisation to Mala s 6 was the second most common, at 4.06%
• 3.28% showed a combined sensitivity to Alt a 1 – Asp f 3
• Pen ch and Cla h extracts stimulated the production of the lowest median sIgE levels
• The highest median sIgE levels were for Alt a 1, Mala s 11 and Asp f 6
• Median sIgE levels increased in adults compared to children for all Aspergillus fumigatus components, as well as for Mala s 5 and Mala s 11, but decreased for the other allergens
• The sensitisation rates to fungi in general and specifically to Alternaria were lower in the western parts of Ukraine, especially in the Carpathian region
• Bayesian modeling showed a 92.42% probability that sensitisation to Alt a 1 occurs when sensitivity to Cla h 8, Mala s 11, Mala s 5, and Mala s 6 is absent
• A lack of sensitivity to one allergen often coincided with others, suggesting independent sensitisation to different fungal allergens

Conclusion:

This study showed that Alt a 1 sensitivity was predominant, with lower rates in the western regions of Ukraine. The highest median sIgE levels were induced by Alt a 1, Mala s 11 and Asp f 6. Bayesian analysis indicates a strong likelihood that sensitisation to different fungal allergens occurs independently. The idea that sensitisation to one allergen may be protective against sensitisation to others requires further investigations.

Summary:

In a study of grass pollen allergy patients in Ukraine, sensitisation to the major allergens Phl p 1 and Lol p 1 was common, with Cyn d 1 also being frequently observed. Additionally, Phl p 2, Phl p 5.0101, and Phl p 6 were identified as genuine markers of grass pollen sensitisation. The combination of Lol p 1 and Phl p 1 was the most frequent profile, potentially with Lol p 1 playing a significant role. Sensitivity to Phl p 2 was the second most common and was found to develop independently. Monosensitisation to Cyn d 1 suggested the influence of climate change, leading to changes in sensitisation patterns.

Rodinkova V, Yuriev S, Mokin V, Sharikadze O, Kryzhanovskyi Y, Kremenska L, Kaminska O, Kurchenko A. Sensitization patterns to Poaceae pollen indicates a hierarchy in allergens and a lead of tropical grasses. Clin Transl Allergy. 2023 Aug;13(8):e12287. doi: 10.1002/clt2.12287. PMID: 37632241; PMCID: PMC10405149.

In a huge patient cohort of more than 10,000 patients from Ukraine, the molecular sensitisation profile to house dust mites was determined with ALEX2 Allergy Explorer. Sensitisation to at least one HDM allergen has been established in 2875 people (27%). The number of sensitised children was 2.26 times higher than that of adults: 69% children vs 31% adults.

Patients were grouped by their sensitisations. Sensitisations to group 2 allergens (Der f 2 – 73%, Der p 2 – 72%) were the most common among the entire group, followed by polysensitisation to group 1 (Der p 1 – 55%, Der f 1 – 54%), group 2 (Der p 2, Der f 2) allergens and Der p 23 (56%). Sensitisations to Der p 21 was found in 27%, to Der p 5 in 28% and to Der p 7 in 23% of the patients. Lowest sensitisation levels were registered for: Der p 20 (8%), Der p 10 (6%) and Der p 11 (0.6%).

To conclude, the key sensitising HDM allergens in Ukraine are Der p 2 and Der f 2. The second most prevalent among adults is monosensitisation to Der p 23, and among children polysensitisation to group 1, group 2 allergens and Der p 23.

doi: 10.3389/fimmu.2022.848616

Rostaher A et al, Animals (Basel), 2023; doi: 10.3390/ani13193002

Background

Hymenoptera venom allergy in dogs can lead to severe, life-threatening anaphylactic reactions following stings from bees, wasps, or ants. Venom immunotherapy (VIT) is the only known treatment to prevent further systemic responses. This study aimed to evaluate the safety and efficacy of VIT in ten dogs with a history of anaphylaxis following repeated Hymenoptera stings, all of which had positive intradermal tests for bee and/or wasp venom and elevated allergen-specific IgE levels. Allergen-specific IgE levels to bee and wasp allergen extracts were measured using the Allercept test. Additionally, the PAX (Pet Allergy Xplorer) test was used to measure specific allergen components including nApi m 1, rApi m 10, rApi m 2, rApi m 3, rApi m 5, rVes v1and rVes v 5.

Key findings:

• In both Allercept and PAX, bee-specific IgE levels were significantly higher than wasp-specific IgE levels
• Most bee-allergic dogs showed sensitisation to Api m 1, 2, 3, and 10, with no dogs showing sensitisation to Api m 5
• Nine dogs with a history of anaphylaxis to a single insect species were found to be sensitised to both bee and wasp allergens when all test modalities were considered
• Allergens used in VIT, based on history and allergological work-up, included bee (8 dogs), wasp (1 dog), and both (1 dog)
• No systemic adverse events occurred during the induction and maintenance phases
• VIT efficacy was assessed by observing clinical reactions to re-stings: of the seven re-stung dogs, only one developed mild angioedema at the sting site, while the others remained asymptomatic

Conclusion:

This study confirmed that VIT is a safe and effective treatment for Hymenoptera-allergic dogs, demonstrating efficacy similar to that in humans. Furthermore, both skin testing and sIgE tests were reliable in identifying the underlying insect sensitisation in these dogs.

Summary:

This is the first paper documenting the use of the Pet Allergy XplorerTM in dogs with hymenoptera-venom induced anaphylaxis: Hymenoptera allergens, such as bee and wasp stings, can trigger anaphylaxis in both dogs and humans. While venom-specific immunotherapy (VIT) is an effective treatment for preventing life-threatening reactions in humans, there's a lack of prospective clinical data on its efficacy in dogs. This uncontrolled prospective clinical trial involved 10 dogs with a history of anaphylaxis due to Hymenoptera stings. The sensitization to bee and wasp allergens was demonstrated by intradermal testing (IDT) and allergen-specific IgE serology (Allercept®, Pet Allergy XplorerTM). As reported by the owners, 8 out of 10 dogs had a history of allergic reactions to bee stings, one dog was stung by a wasp, and one dog had a history of bee and wasp stings. All 10 dogs tested positive in IgE Allercept® and 9 out of 10 dogs in the PAX® serology test. When correlating the data of both serological tests, a statistically significant moderate positive correlation was found (r = 0.62, p = 0.028) for bee allergens. Eighty percent of the dogs (8/10 dogs) tested positive for CCD IgE, as determined by Allercept® test, only two dogs were negative for these specific antibodies. The levels of bee- specific IgEs were significantly higher than the wasp-specific IgE for Allercept® (median 350 vs. 30 HERBU/mL, p = 0.007) and PAX test (median 182 vs. 27 ng/mL, p = 0.003). Most of the bee-allergic dogs were sensitized to the following allergen components: Api m 1, Api m 2, Api m 3, and Api m 10. None of the dogs were sensitized to Api m 5. As there were only two dogs allergic to wasps, the dataset for the allergen components was too small for statistical analysis. VIT was administered in an induction phase followed by monthly maintenance injections, and it proved to be safe with no systemic adverse events. Among the re-stung dogs, only one developed mild angioedema, while the rest remained asymptomatic. These findings demonstrate that VIT is a safe and effective treatment for Hymenoptera-allergic dogs, potentially preventing anaphylactic reactions.

https://pubmed.ncbi.nlm.nih.gov/37835609/

Scala E et al; Eur Ann Allergy Clin Immunol, 2023; doi: 10.23822/EurAnnACI.1764-1489.314

Background

Non-specific lipid transfer proteins (nsLTPs), which are important food and environmental allergens, are especially prevalent in areas with high plant food intake. Initially believed to be confined to the Mediterranean area, LTP IgE reactivity is now known to be widespread, with variations in epitope recognition among different populations, indicating the potential impact of individual, environmental, and dietary factors. This study aimed to investigate the individual LTP molecular recognition profiles, clinical outcomes, and potential influencing external factors in an Italian population with IgE reactivity to at least one of 15 LTPs. A total of 1,831 patients were screened using ALEX², and the 426 patients who exhibited at least one LTP reaction were included in the study.

Key findings:

• Most common sensitisations were to: Pru p 3 (77%), Mal d 3 (60%), Zea m 14 (60%), Ara h 9 (50%), Pla a 3 (50%)
• In the studied population, Pru p 3 remains the molecule most commonly associated with LTP allergy however, the results showed that Pru p 3 is less effective in detecting patients at high risk for severe reactions than specific sensitisations to Cor a 8, Mal d 3, or Arah 9
• 234 patients (54.9%) were solely sensitised to LTPs, while the remaining individuals were also sensitised to other pan-allergens: 118 (27.7%) to PR10, 56 (13.1%) to profilin, and 23 (5.4%) to polcalcin
• Higher sIgE levels and concurrent sensitisation to >5 allergen molecules were significantly associated with an increased risk of severe reactions
• Influence of co-factors on clinical outcomes:
• Co-factors associated with an increased risk of severe reactions: mono-reactivity to LTP (44.6%; p=0.001), FDEIA (10.8%; p=0.001), and FDNIH (11.5%; p=0.005)
• Co-factors associated with decreased symptom severity: reactivity to PR10 (24.2%; p=0.001), profilin hypersensitivity (10.3%; p=0.001), and/or atopic dermatitis (16.7%; p=0.001)

Conclusion:

In conclusion, LTP syndrome severity is linked to a broader IgE repertoire and higher IgE levels. Ara h 9, Cor a 8, and Mal d 3 were strongly associated with more severe symptoms. Further, co-factors such as FDEIA, FDHIH, and LTP monoreactivity can worsen patient clinical outcomes, while atopic dermatitis and co-sensitisation to profilin and/or PR10 can improve them. Thus, these co-factors can aid in the daily clinical management of LTP syndrome.

Scala E et al; J Investig Allergol Clin Immunol Vol. 35(3), 2024; doi: 10.18176/jiaci.0986

Background

Edible insects are considered the next super global food as it provides a rich source of protein and micronutrients, despite the risk of anaphylaxis. In this study, the IgE-mediated sensitisation status of three insects (cricket, locust, and mealworm) in patients never knowingly consumed edible insects before was assessed. A total of 2,014 participants were screened with ALEX² for the extracts Acheta Domesticus (Ad), Locusta migratoria (Lm), and Tenebrio molitor (Tm).

Key findings:

• 9.7% participants were sensitised to insects, but none of these had knowingly consumed edible insects in the past
• 46% showed reactivity to all three extracts, and the mono-sensitisation rates were 18% for Ad, 15% for Tm, and 3% for Lm
• 40-60% showed sensitivity to allergenic components found in crustaceans, molluscs, and nematodes: Tropomyosin was co-recognised by 34%, and arginine kinase by 18.5%; <5% showed reactivity to Sarcoplasmic-CB, Troponin-C, Paramyosin, or Myosin-light-chain; 55.4% did not show any reactivity to invertebrate pan-allergens
• 16.9% experienced mono-sensitisation exclusively to insects
• Arachnid reactivity was inversely proportional to insect allergen sensitisation, while Mollusca, Blattoidea, and tropomyosin reactivity displayed a direct relationship
• Myosin-light-chain reactivity correlated with Ad and Lm, and Troponin-C with Ad and Tm sensitisation

Conclusion:

Many individuals with IgE sensitisation to edible insects had no prior exposure to them, leaving the cause of sensitisation unclear. This study revealed a direct link between insect sensitisation and reactivity to tropomyosin, mollusks, and cockroaches, suggesting these as primary sensitisers. With the growing acceptance and popularity of edible insects as a novel food source, it is crucial to address their potential allergenicity and related health concerns.

In the present study, a cohort of 140 allergic individuals presenting distinct clinical phenotypes (e.g., atopic dermatitis, adverse food reactions, allergic rhinitis, bronchial asthma) were analysed by two different in-vitro diagnostic allergy tests - Allergy Explorer-ALEX2® and ImmunoCAP ISAC112®. A significant conformity was observed when dichotomised data (94.3% concordant results) were analysed. Especially for species-specific marker allergens - perfect correlations were detected. The Allergy Explorer ALEX2® test includes a larger number of allergens, allowing a broader molecular detection. Furthermore, the presence of several allergens only on ALEX2® revealed as an important feature. However, heterogeneous results emerged comparing panallergens.

doi: 10.1111/cea.14016

Summary:

Since not all patients with shellfish allergies experience adverse allergic symptoms after mollusk ingestion, this multicenter study aimed to investigate the sensitization profile of 247 individuals with self-reported adverse reactions to shrimp with or without cross-reactivity to mollusks. Of these, 48% reported an adverse reaction to mollusks ingestion. Patients underwent skin prick testing, and the IgE-reactivity was measured using the in-vitro Allergy Xplorer ALEX2. The ALEX2 test was chosen, because it enables the broad evaluation of shellfish allergens, including Pen m 1 (tropomyosin), Pen m 2 (arginine kinase), Pen m 3 (myosin light chain), and Pen m 4 (sarcoplasmic calcium-binding protein) all from Black-Tiger shrimp (Penaeus monodon), Cra c 6 (the troponin-c from brown shrimp, Crangon crangon), Der p 10 (tropomyosin), and Der p 11 (paramyosin) both from Dermatophagoides pteronyssinus, as well as of shellfish extract including crab, lobster, northern shrimp, white shrimp, squid, mussel, oyster, clam, and scallop. Among the patient group reactive to mollusks, the allergens Pen m 1, Pen m 2 and Pen m 4 dominated, compared to mollusk tolerant subjects. Kiwi allergy in atopic dermatitis patients – analysis of specific IgE results in ALEX2 multiplex examination.

DOI:https://doi.org/10.1016/j.waojou.2022.100685

Summary:

In the present study, in-vitro IgE tests using molecular components represent important innovations in the diagnosis of rare diseases, such as inborn errors with HIE (Hyper-IgE). Thus, IgE sensitisation profiles can be evaluated, even in cases in which the patient’s cognitive defect does not allow for correct allergological classification. The use of allergen multiplex tests improves both, the management of skin pathology and the quality of life of the individual patients.

Here, a proteomic test combined with IgE testing were performed to study inborn errors with an atopic dermatitis-like clinical picture associated with a deregulated IgE response. Four patients with rare diseases, such as recessive X–linked ichthyosis, Comel–Netherton syndrome, monosomy 1p36 syndrome, and a microduplication of Xp11.4 associated with extremely high levels of IgE were evaluated by comparative genomic hybridisation microarray analysis and specific IgE evaluation using allergen macroarray (ALEX2) and allergen microarray (ISAC).

In patients suffering from atopic dermatitis, IgE reactivity to LTP-related food allergens was detected, impacting the quality of life. The avoidance of LTP-related foods from the diet resulted in a marked improvement of the patient’s clinical condition.

Furthermore, reactivity to CCDs (Cross-reactive carbohydrate determinants) was evidenced in one patient. Although sensitisation to CCDs has no clinical impact, it is important to remember that IgE testing without blocking CCD-specific IgE antibodies can give false IgE test results.

In another patient, reactivity to autoreactive allergenic components was shown. Interestingly, the patient was positive for both Asp f 6 and Ole e 9 considered to be a signature of patients with atopic dermatitis in the Mediterranean area.

To identify patterns of IgE sensitisation in patients with atopic dermatitis, ImmunoCAP ISAC® and Allergy Explorer‐ALEX® microarray analysis were performed. The olive tree pollen β‐1,3‐glucanase rOle e 9 and the manganese superoxide dismutase from Aspergillus rAsp f 6 were the molecules most significantly associated with AD occurrence and allowed to discriminate among the moderate and severe forms of disease. This publication demonstrates the importance of allergy tests using a large panel of molecular components to unveils important associations between IgE reactivity profiles and AD clinical presentation.

doi: 10.1111/cea.13555

Sekerel BE et al; Pediatr Allergy Immunol 35(6):e14177, 2024; doi: 10.1111/pai.14177

Background:

Recently, numerous allergen molecules (AMs) associated with animal sensitisations have been identified, unveiling significant co- and cross-sensitisation patterns among these apparently distinct allergens. This study aimed to better understand co-, cross-, and genuine sensitisations. Furthermore, the impact of age and accompanying allergic diseases on sensitisation profiles was elucidated. A total of 313 children with multiple allergies were tested by ALEX2 multiplex allergy test and 120 children, sensitised to at least one of the 14 AMs from cat, dog, or horse included were included in the study. Relationships between sensitisations were explored through correlations and hierarchical clusters.

Key findings:

• Fel d 1, Can f 4/5, and Equ c 4 may represent genuine sensitisations for their respective animals, as they differ from other cat, dog and horse AM sensitisations
• Correlations were found between lipocalins (Can f 1/2/6, Fel d 4/7, Equ c 1), serum albumins (Fel d 2, Can f 3, Equ c 3), and uteroglobins (Fel d 1, Can f_Fd1)
• Hierarchical clustering of sensitisation revealed two similarity and one dissimilarity cluster, estimating cross-reactivity likelihood
• Potential increase in sensitisation to animal AMs alongside rising sensitisation to other aeroallergens with advancing age
• No significant difference detected for the presence or absence of various types of allergic comorbidities

Conclusion:

The use of correlations and hierarchical clustering can unveil the extent of co-, cross- and genuine sensitization relationships among animal AMs. The insights gained from this study have the potential to enhance diagnostic accuracy and improve artificial intelligence algorithms.

Summary:

The effect of IgG depletion on sIgE levels was determined with two allergen multiplex tests, the ALEX2 Allergy Xplorer and the ImmunoCAP ISAC. The authors report direct evidence that IgG competition hampers sIgE binding. The impact of IgG competition on sIgE levels to molecular allergens was stronger for food than for airborne molecules. Furthermore, IgG competition can completely block sIgE binding, resulting in false negative reports which needs to be considered for allergen multiplex-based precision medicine approaches.

DOI: 10.1111/all.14536

Summary:

The goal of the study was to characterise the clinical and molecular sensitisation profile of a population of peach-allergic patients and to identify possible sensitisation profiles which are associated with severe reactions in the Mediterranean area.

A group of 20 adult patients with peach-allergic reactions, both positive for SPT and sIgE for peach were recruited.

Pru p 3 was the most prevalent LTP found in the study. Patients with systemic reactions from the cohort had significantly higher sIgE levels for LTP allergens compared to patients with local reactions. Coherent with literature, sIgE found for Pru p 3, Mal d 3, Ara h 9 and Pla a 3 were related to the occurrence of systemic reactions. LTPs from pollen were identified in the cohort, showing possible cross-reactivity. Sensitisation to other panallergens than LTPs were identified: PR-10 was positive in two patients belonging to the local reaction group. Profilin was identified in one patient from the systemic reaction group. Overall, the molecular profile characterisation seems a useful marker of disease expression in peach-allergic patients. Additionally, the authors state that ALEX² reduces time spent by performing simultaneous IgE measurements and helps identifying sensitisation patterns associated with systemic reactions.

http://doi.org/10.23822/EurAnnACI.1764-1489.284

Summary:

This study compared the ALEX2 Allergy Xplorer and the ImmunoCAP ISAC multiplex arrays in atopic children by relating their sensitization profile to clinical data. Good overall agreement was found for egg, cow’s milk, peanut, codfish/prawn, soy and wheat components. Comparing both tests, the ALEX test provides more sIgE results, including whole extracts and components helping clinicians to study cross-sensitization patterns.

DOI: 10.1186/s12948-022-00177-w

Storz L et al; Front Med (Lausanne) 11:1353784, 2024; doi: 10.3389/fmed.2024.1353784

Background

Atopic dermatitis (AD) is a chronic inflammatory skin condition, affecting 15-30% of children and 2-10% of adults. Although AD is linked to sensitisation to various allergens, the role of the fungal microbiota (mycobiota) in disease severity remains poorly understood. The objective of this study was to examine the specific sensitisation towards the mycobiota in AD patients, with respective to their fungal skin colonisation and to analyse how the mycobiota impact the disease severity. The sensitisation patterns towards the two most common fungal microorganisms on human skin, Malassezia spp. and Candida albicans were investigated in 16 AD patients and 14 healthy controls (HC) over 18 years old in Switzerland using ALEX² and ImmunoCAP.

Key findings:

• There was a significant difference in tIgE between AD and HC patients in both ALEX² and ImmunoCAP
• There was a significant difference in M. sympodialis Mala s 6 sIgE (ALEX2) as well as C. albicans m 5 sIgE (ImmunoCAP) between HC and severe AD patients as well as between mild to moderate AD and severe AD
• There was a statistically significant correlation between disease severity and sensitisation pattern: sensitisation of Malassezia spp. and C. albicans is increased in AD patients compared to HC
• Malassezia spp. abundance decreased in severe AD compared to HC and mild to moderate AD
• Candida spp. abundance increased in severe AD when compared to HC and mild to moderate AD

Conclusion:

This study revealed that AD, especially in severe cases, is linked to increased sensitisation towards the host’s mycobiota. Candida spp. skin colonisation positively correlates with AD. Malassezia spp. colonisation showed a negative correlation with AD, AD severity and sensitisation patterns.

Tuten Dal S et al; Pediatr Allergy Immunol 35(2):e14093, 2024; DOI: 10.1111/pai.14093

Background:

Mites are common global aeroallergens. House dust mites (HDM) produce various molecular allergens (MA), which can elicit specific immune responses in sensitised individuals, causing distinct clinical symptoms. Understanding an individual's mite allergen sensitisation profile is essential for diagnosing and managing mite allergic diseases. The objective of this study was to investigate the MA sensitisation patterns among mite-sensitised children. For this purpose, 76 Turkish children with sensitisation to at least one mite MA were selected and the age-specific characteristics as well as potential cluster relationships among sensitisation patterns were investigated.

Key findings:

• 313 children were tested for their MA-sensitisation pattern by ALEX²
• 76 children showed sensitisation to at least one mite allergen molecule and were included in the study
• 69.7% of patients experienced co-sensitisation to other aeroallergens; namely 52.6% to tree pollen, 43.4% to grass pollen and 23.7% to weed pollen
• Increasing co-sensitisation with other aeroallergens as patient’s age advanced
• Most common sensitisations were to Der p 1/2 and Der f 1/2 (around 40%)
• Der p 10/Blo t 10, Der p 20, Der p 23, and Gly d 2/Lep d 2 showed approximately 20% sensitisation rate
• Der p 23 sensitisation rates and specific-IgE levels increased with age
• Hierarchical clustering confirmed the strong correlations between Der f 2 and Der p 2, Der p 10 and Blo t 10, Der p 21 and Blo t 5, and Gly d 2 and Lep d 2
• Der p 10 and Blo t 10-sensitive patients were mostly seen as mono sensitisation

Conclusion:

This study reveals an age-related increase in both the diversity and intensity of mite sensitisations in children, especially for Der p 23. Significant correlations among these sensitisations emphasises homologies among specific MAs. Furthermore, in the studied population a significant portion of mites sensitisation originated from tropomyosin and arginine kinase.

Ukleja-Sokołowska N et al; Adv Dermatol Alergol 40(5):661-669, 2023; doi: 10.5114/ada.2023.132071

Background:

With shrimp sensitisation becoming more prevalent in developed countries, accurate diagnosis is critical. This requires selecting the most effective diagnostic method and tailoring the strategy to each patient’s unique clinical situation. This study aimed to investigate the allergen profile of shrimp-sensitised patients. For this purpose, 50 patients with positive prick-to-prick tests with tiger shrimp and with elevated specific IgE levels to shrimp extract in ImmunoCAP were studied using ALEX2, which allows to access specific IgE to shrimp allergen extracts and shrimp allergen components.

Key findings:

• 50 adult patients with positive prick-by-prick test and 35 patients with negative skin prick test (= control group) were included in the study
• In the sensitised group, 22 patients were sensitised to at least one allergen component of Penaeus monodon, 20 to crab, 20 to lobster, 15 to Northern prawn and 12 to Shrimp mix (Litopenaeus setiferus, Farfantepenaeus aztecus, Farfantepenaeus dourarum)
• The most prevalent shrimp allergen in the group of patients studied was tropomyosin, Pen m 1, followed by aginine kinase
• Potential cross-sensitisations between shrimp tropomyosin Pen m 1 and Anisakis simplex tropomyosin Ani s 3 as well as Pen m 1 and American cockroach Per a 7 (Spearman’s Rank Correlation = 0.98)
• 41 patients were co-sensitised to at least one house dust mite allergen component
• House dust mite (HDM) sensitisation was significantly higher in the shrimp sensitisation group
• Most common HDM sensitisations were to Der p 2 (66%), Der p 23 (54%), Der p 5 (52%), and Der p 1 (52%)

Conclusion:

ALEX² offers a thorough overview of a patient's allergen profile because includes a largen number of shrimp allergen extracts and components. In this study, the most prevalent shrimp sensitisation was to shrimp tropomyosin (present in 34% of patients). This might imply that there are other shrimp allergen components responsible for sensitisation, which are not reflected in ALEX². Sensitisation to HDM is an important problem in shrimp-sensitised patients and patient sensitised to shrimp showed to have sensitisation also to other types of seafood.

Summary:

This study evaluated the prevalence of IgE responses towards a comprehensive panel of house dust mite (HDM) allergens using the ALEX2 Allergy Xplorer. Thus different serological reactivity profiles were found to be associated with different clinical manifestations. Interestingly, asthmatic patients with HDM allergy recognize a larger spectrum of allergens, especially the prevalence and the level of sIgE to Der p 5, Der p 7, Der p 20 and Der p 21 were higher in asthmatic patients, whereas sensitization to fewer components is more related to rhinitis. Group 1 and group 2 allergens as well as Der p 23 were identified as seroprevalent as well as serodominant representing allergens that quantitatively make the most important contribution to HDM IgE response. However, the most interesting novelty offered by this study using the ALEX2 test is the possibility to determine IgE reactivities toward major and minor HDM allergens. Interestingly, 51% of the evaluated patients scored positive for at least one minor allergen with a high prevalence for Der p 5 (26%), Der p 7(28%), Der p 20 (14%) and Der p 21 (30%). The rate of IgE reactivity to Der p 10 and Der p 11 was very small, 6% and 1%, respectively. The differences in IgE reactivities to minor HDM allergens might be explained by different routes of sensitization. Der p 5, Der p 7, Der p 20 and Der p 21 are mainly present in faecal particles sensitizing through the respiratory tract. In contrast, Der p 10 and Der p 11 are mainly found in the HDM body sensitizing preferentially through the skin or the gut due to cross-reactivities with homologous food allergens, in the case of Der p 10.

DOI: 10.23822/EurAnnACI.1764-1489.195

Since fish allergy diagnosis is still an important challenge for allergists, the present study aimed to evaluate the diagnostic sensitivity of an in-vitro multiplex assay, the ALEX² Allergy Xplorer, using a comprehensive panel of fish allergens and the cross-reactivity patterns between different molecular components in 56 fish allergic patients.

The ALEX² Allergy Xplorer was used to assess a broad sensitisation profile of fish allergens including ß-parvalbumins from cod (Gadus morhua- Gad m 1), carp (Cyprinus carpio- Cyp c 1), herring (Clupea arengus- Clu h 1), salmon (Salmo salar- Sal s 1), mackerel (Scomber scombrus- Sco c 1), tuna (Thunnus albacares- Thu a 1) and swordfish (Xiphias gladius- Xip g 1), α-parvalbumin from thornback ray (Raja clavata- Raj c-parvalbumin), and aldolase + enolase from cod (Gad m 2 + 3). The single ß-parvalbumins Clu h 1, Cyp c 1, Gad m 1, Sal s 1, Sco s 1, Thu a 1 and Xyp g 1 scored positive in 75.0%, 67.8%, 62.5%, 80.3%, 80.3%, 78.8% and 73,2% patients, respectively. 14.3% scored positive for the α-parvalbumin (Raj c-parvalbumin), and 16.1% for the aldolase + enolase (Gad m 2 + 3) components. 92.8% reacted to at least one ß-parvalbumin and 96.4% to at least one of the allergens tested. Overall sensitivity was higher than the sensitivity obtained using commercial extracts of cod, salmon, and tuna for skin prick test (75.8%) and IgE detection (92.3%).

To conclude, the ALEX² allergy test revealed a high diagnostic sensitivity, and it is therefore an essential tool to investigate the cross-reactivity patterns between different molecular components and furthermore looking for potentially safe fish species.

doi: 10.1016/j.cca.2022.06.010

Specific IgE reactivity to a comprehensive panel of house dust mite allergens such as Der f 1, Der p 1, Der f 2, Der p 2, Der p 5, Der p 7, Der p 10, Der p 11, Der p 20, Der p 21 and Der p 23 was tested in patients with respiratory symptoms using Allergy Explorer (ALEX2®). Prevalence and IgE levels of Der f 1, Der f 2, Der p 1 and Der p 20 were significantly higher in asthmatic patients, whereas subjects negative for minor allergens resulted more frequently suffering from rhinitis. Asthmatic patients had IgE reactivity to a larger number of HDM allergens than patients with only rhinitis.

doi: 10.23822/EurAnnACI.1764-1489.195

Summary:

In this study, the ALEX2 Allergy Xplorer was used to assess the spectrum and frequency of sensitization to food allergens in patients suffering from allergic rhinitis. 75% of the patients demonstrated co-sensitization to at least one food allergen: • Hazelnut (28%) • Apple (26%) • Peanut (22%) • Celery (14%) • Soy (13%) • Fish carp (11%) etc. Interestingly, the frequency of sensitization to cross-reactive proteins PR-10 was 21% in patients with allergic rhinitis without food co-sensitization compared to 51% in patients suffering from both, allergic rhinitis and food sensitization.

DOI: https://doi.org/10.21203/rs.3.rs-1823124/v1

Walsemann T et al; Allergy 78(3):731-742, 2023; doi: 10.1111/all.15553

Background

House dust mites (HDM) are a major source of airborne allergens, affecting one in five EU citizens and significantly contributing to allergic asthma and atopic dermatitis. This study aimed to identify potential biomarkers by investigating the relationship between various HDM allergens and allergic rhinitis, asthma, and atopic dermatitis. The clinical relevance of nine HDM allergens (nDer p 1, rDer p 2, rDer p 5, rDer p 7, rDer p 10, rDer p 13, rDer p 20, rDer p 21, rDer p 23) were evaluated by analysing sensitisation patterns in 384 HDM-allergic adults exhibiting different clinical phenotypes.

Key findings:

• Grouping of patients according to clinical phenotypes: single or combined presence of allergic asthma (AA), atopic dermatitis (AD) and allergic rhinitis (AR) ranked after sensitisation count and disease severity
• The number of allergen sensitisation increased with clinical phenotype severity
• Sensitisation to more than 3 HDM allergens associated with the occurrence of multiple allergic diseases
• Sensitisation to more than 3 HDM allergens significantly associated with allergic asthma and/or atopic dermatitis
• Sensitisation to 3 or less HDM allergens mainly associated with AR
• AA patients were more often sensitised to Der p 5 and 21 compared to AR
• AD patients were more often sensitised to Der p 2, 5, 10, 13, 20, and 21
• Der p 20 – a biomarker for severe AD: Der p 20-IgE > 80 kU/L strongly associated with severe AD in 75% of patients

Conclusion:

This study underscores the clinical importance of both the total sensitisation count and specific allergens such as Der p 5, 20, and 21 which, are not available for routine diagnostics. Incorporation of those allergens in routine diagnostics along with the sensitisation count should enhance the diagnosis and risk assessment of HDM-allergic patients. In addition, the study concludes that HDM-multiplex test is a good diagnostic tool and carries an advantage over ImmuoCAP by requiring only a small amount of serum per analysis.

Summary:

Using the ALEX2 allergy test, which tests the largest number of mite molecules, the house dust mite sensitization profile was evaluated in a data set of 20 033 Ukrainian patients. Aim of the study was to apply these results on targeted treatment strategies of HDM allergy. Allergic disease in the anamnesis (allergic rhinitis, atopic dermatitis, bronchial asthma) was the inclusion criterion in the study. To determine the probability of developing sensitization to certain molecular HDM components, a Bayesian network was constructed.

General findings of the study:

• Sensitization to at least one HDM allergen was detected in 26% of the total study population

• Ukrainians were most often sensitized to HDM allergens of groups 1 and groups 2 as well as Der p 23

• HDM sensitization patterns:

1. Der f 2 (72%), Der p 2 (72%)
2. Der p 23 (55%)
3. Der f 1 (55%), Der p 1 (53%)
4. Der p 5, Der p 21, Der p 7, Der p 20, Der p 10, Der p 11

• Sensitization to HDM allergens among different age groups

1. Sensitization to group 1 allergens is higher than group 2 allergens sensitization, which might be explained by the fact that Der p 1 can be found in breast milk

2. 1 year: decrease in sensitivity to group 1 allergens, increased sensitivity to group 2 allergens

3. Der p 23 sensitization remains significant in all age groups
4. Der p 5, Der p 7 and Der p 21 sensitivity becomes pronounced starting from the age of 3-6 years
5. Lowest incidence of sensitivity was observed to Der p 10, Der p 11 and Der 9 20

• Results of the Bayesian Network analysis of personal profiles indicated the leading role of Der p 1 and Der f 2 and that the leading role in the formation of sensitivity to group 5 allergens may belong to Der p 21.