Component-resolved Diagnostics Research Articles

When allergies have no name: is idiopathic anaphylaxis driven by co-factors?

Idiopathic anaphylaxis (IA) is a severe allergic reaction without identifiable external triggers, presenting significant challenges in diagnosis and management. However, growing evidence suggests that many cases classified as idiopathic may actually be driven by cofactors such as exercise, hormonal fluctuations, medications, or hidden allergens. This mini-review explores the evolving understanding of IA, highlighting the role of these cofactors in triggering or amplifying anaphylactic reactions. It emphasizes how advances in diagnostic tools, including component-resolved diagnostics, are helping to identify previously undetected allergens, leading to more accurate diagnoses and reducing the prevalence of true idiopathic cases. As our knowledge of anaphylaxis and its underlying mechanisms deepens, the need for comprehensive evaluations that account for cofactor involvement becomes increasingly clear. Continued research in this area is essential to improve patient outcomes and better manage this complex condition.

Component-resolved diagnostics of fruit and vegetable allergy: precise identification and individualized treatment strategies

Vegetable and fruit allergies are common types of food allergies worldwide, most of them are triggered by primary sensitization to pollen. Most allergens in vegetables and fruits belong to a few cross-reactive proteins such as PR-10 proteins, profilins, and nsLTPs. The presence of these allergens in various plants can lead to widespread cross-reactive allergic responses. Component-resolved diagnostics (CRD) can improve diagnostic accuracy by precisely identifying specific allergenic proteins, aiding physicians in making more accurate treatment and management decisions, and reducing unnecessary food avoidance. This article, based on the "Molecular Allergology User's Guide 2.0 (MAUG 2.0)" issued by the European Academy of Allergy and Clinical Immunology (EAACI), analyzes the primary mechanisms, relevant allergens, and diagnostic and clinical management strategies for vegetable and fruit allergies. By detailing and analyzing these allergenic components, this article may help the healthcare professionals to deep the understandings of vegetable and fruit allergies, offer new perspectives and practical guideline for the research and treatment of these allergies, and promot the development of precise diagnostics and personalized treatment strategies.

Recent Advances in Allergic Rhinitis: A Narrative Review.

Allergic rhinitis (AR) is a prevalent chronic respiratory condition characterized by nasal inflammation, sneezing, congestion, and itching, significantly impacting quality of life. Over recent years, considerable advancements have been made in understanding the pathophysiology, diagnosis, and management of AR. This narrative review aims to synthesize these recent developments, providing a comprehensive overview of key areas. Emerging insights into AR pathophysiology have elucidated the complex interplay between genetic predisposition, environmental factors, and immune system dysregulation. Notably, the role of the epithelial barrier and the microbiome in AR pathogenesis has garnered increasing attention, offering potential targets for novel therapies. Advances in diagnostic technologies, such as component-resolved diagnostics and molecular allergology, have enhanced the precision of allergy identification, enabling more personalized treatment approaches. In terms of management, significant progress has been made in pharmacological and non-pharmacological treatments. Novel biologics targeting specific pathways involved in AR, including monoclonal antibodies against immunoglobulin (Ig)E and interleukin (IL)-4/13, have shown promise in reducing symptoms in refractory cases. Additionally, there has been a resurgence in interest in non-pharmacological strategies, including allergen avoidance, immunotherapy, and complementary therapies, which offer holistic options for patient care. The integration of digital health tools and mobile applications in AR management has further empowered patients, allowing for real-time symptom tracking and personalized treatment adjustments. Recent guidelines emphasize a multidisciplinary approach to AR management, promoting integrated care models that involve collaboration between allergists, primary care providers, and other specialists. These guidelines also highlight the importance of patient-centered care, advocating for shared decision-making and tailored treatment plans based on individual patient profiles. In conclusion, the landscape of allergic rhinitis management is rapidly evolving, with ongoing research and innovation paving the way for improved outcomes. This review underscores the importance of staying abreast of these advances to optimize the care and quality of life for individuals affected by allergic rhinitis.

The Diagnosis of Allergy to Lipid Transfer Proteins.

To provide an update on the diagnosis of non-specific Lipid Transfer Protein (nsLTP) allergy. More publications report the presence of nsLTP allergy in Northern European countries and nsLTP sensitisation in children. Individuals are more likely to have severe reactions if there is recognition of increasing numbers of LTP components. Diagnosis is problematic; not all those with nsLTP allergy will have a positive test to a peach extract containing Pru p 3, the peach nsLTP. Sensitisation to nsLTP is being reported in more countries, including to the nsLTP in Cannabis Sativa in North America. Meals containing multiple nsLTP foods are more likely to be involved in co-factor reactions. Component-resolved diagnostics are superior to skin prick tests, to determine sensitisation to the individual nsLTP allergens causing symptoms and, in the future, the Basophil Activation test may best discriminate between sensitization and clinical allergy.

A Novel Quality Control Strategy for the Preparation of High-Quality Recombinant Allergens in Escherichia coli: A Case Study of Der f 2

Introduction: Recombinant allergens produced by Escherichia coli (E. coli) system play an important role in the component-resolved diagnostics of allergy and vaccine development. However, incorrect folding of recombinant allergens may affect their application. Therefore, it is very important to monitor the correct folding of recombinant allergens. Currently, there is still a lack of a quality control strategy to solve this problem. In this study, a mite allergen, Der f 2, was taken as an example to establish a novel quality control strategy, which was based on chromatography to isolate the allergen, and on enzyme-linked immunosorbent assay to verify the IgE reactivity of the isolated allergen. Methods: The nucleotide sequence encoding Der f 2 was codon-optimized and cloned into pET-28a (+) plasmid. Best conditions for the expression of Der f 2 in E. coli were sought. The inclusion body of Der f 2 was denatured and purified by nickel affinity chromatography. Refolding processes were compared using glutathione redox system. The fully and partially folded proteins were separated by anion exchange chromatography, and the IgE reactivity of the isolated proteins was verified by indirect enzyme-linked immunosorbent assay. Results: An optimized 387 bp segment of the Der f 2 coding gene was successfully expressed in E. coli. Best induction conditions included preinduction bacterial density with absorbance value at 600 nm was 0.6, 1 mM isopropyl beta-d-thiogalactopyranoside at 28°C for 4 h. The Der f 2 protein after refolding was separated by chromatography and two fractions were obtained. The first fraction was identified as monomer protein and the second as aggregate by size-exclusion chromatography. Indirect enzyme-linked immunosorbent assay also confirmed that the first fraction showed higher IgE reactivity. Conclusion: In this study, a novel quality control strategy based on chromatographic separation and IgE reactivity monitoring was established in the case of mite Der f 2, which systematically evaluated the effectiveness of multiple preparation methods for the first time. It is faster and more convenient when compared with the existing methods such as size-exclusion chromatography. This strategy laid a foundation for the stable application of recombinant allergens produced by E. coli in component-resolved diagnostics and the development of molecular vaccines in the future.

Food Allergy and Food Intolerance – New Developments

It is crucial to accurately identify whether a patient's reaction to food is a result of a Food Allergy (FA) or Food Intolerance (FI), as this will determine the appropriate diagnosis and management plan. Medical practitioners should rely on verified diagnoses when discussing the prevalence of these conditions. Currently, obtaining a patient's clinical history, performing a skin prick test (SPT) or measuring serum specific IgE levels are typically the initial steps in diagnosing allergies. Additional methods, such as component-resolved diagnostics, basophil activation test (BAT) and oral food challenge (OFC) may be used, if available, to confirm the allergen causing symptoms when the results of first-line tests are equivocal or contradictory with history. Determining the prevalence of sensitization profiles to different allergens, considering geographical characteristics, is important for developing personalized therapeutic and preventive measures for children. Periodic reassessment of patients with FA through allergy tests and oral food challenges will allow for the possibility of reintroducing previously avoided foods if they develop tolerance over time and improve their quality of life.

Long-term efficacy and safety of cow’s milk anaphylaxis specific immunotherapy: Allergen unresponsiveness via the Tolerance Induction Program

Tolerance Induction Program (TIP) immunotherapy applies machine learning contextualized on immunologic and food protein data sets. TIP has established efficacy toward peanut allergy. This form of treatment demonstrates equal efficacy toward cow's milk anaphylaxis. TIP maintains remission outcomes defined as a minimum of 7 days of allergen unresponsiveness to high-dose protein exposures. Furthermore, remission patients openly consume unrestricted amounts of dairy protein. We sought to assess the rate of decline in specific IgE specific whole and component-resolved diagnostics following 1 year of TIP milk immunotherapy. The study comprised 214 cow milk anaphylactic children who underwent TIP at the Translational Pulmonary & Immunology Research Center/Food Allergy Institute. Postintervention changes in cow milk specific IgE, component-resolved diagnostics, and specific IgG4 were assessed. After 1 year of 10-g dairy protein weekly sustained unresponsiveness, eosinophil count decreased from 558.38 to 409.26 cells/μL, the mean cow milk IgE decreased from 16.91 to 9.10 kU/L, the mean boiled cow milk IgE decreased from 12.89 to 6.03 kU/L, the mean Bos D4 decreased from 7.38 to 3.52 kU/L, the mean Bos D5 decreased from 6.79 to 3.16 kU/L, and the mean Bos D8 decreased from 13.55 to 6.62 kU/L. Adverse events were rare. TIP cow milk immunotherapy significantly reduced cow milk specific IgE and component-resolved diagnostics while increasing specific IgG4 in cow milk anaphylactic children. TIP demonstrates safety and clinical efficacy in cow milk anaphylaxis treatment.

Advancing allergy diagnosis in children through component resolved diagnostics in a pediatric tertiary care hospital

Advancing allergy diagnosis in children through component resolved diagnostics in a pediatric tertiary care hospital

Skin tests, serological IgE detection, basophil test—what is available, useful and helps to clarify a mold allergy?

AbstractThe prevalence of sensitization to molds is low in healthy people, but significant in asthmatics. As it has not yet been possible to establish a cause-and-effect relationship between the presence of mold allergens and the occurrence of allergic symptoms, there is a great deal of uncertainty. The update of the S2k guideline “Medical–clinical diagnostics for indoor mold exposure” should help to objectify the topic. Based on the recommendations listed there for the diagnosis of suspected IgE-mediated mold allergy, this article presents the possibilities of skin tests, IgE determinations, and other in vitro test options, but also their limitations in clarifying the cause. Potential possibilities include component-resolved allergy diagnostics, while the limitations include the difficult standardization of test allergen extracts due to the complex allergen source and the insufficient commercial availability of the test extracts. A diagnostic algorithm is presented as a tool for a systematic approach to patients with suspected mold-associated respiratory allergy.

Advancing allergy practice in India for respiratory physician

The landscape of allergy practice in India is undergoing transformative changes, shifting from traditional symptom management to embracing advanced diagnostic and therapeutic modalities for disease modification. This evolution is propelled by the integration of subcutaneous immunotherapy, biologic treatments, and the exploration of probiotics, alongside advancements in diagnostic approaches such as component-resolved diagnostics (CRD) and basophil activation tests. Despite the promising potential of these innovations to enhance patient care, their implementation faces challenges, including limited awareness, safety concerns, accessibility, and affordability. Moreover, the development and standardization of allergy diagnostics, such as CRD, along with the establishment of regional pollen calendars, are crucial for improving the precision of allergy care. This abstract underscores the need for overcoming existing barriers and leveraging emerging technologies and treatments to significantly improve the management of allergic diseases in India, aiming for a future where allergies are not just managed but effectively controlled and prevented.

Microfluidic Immunosensing Platform Based on a Rolling Circle Amplification-Assisted DNA Dendrimer Probe for Portable and Sensitive Detection of Allergen-Specific IgE.

The robust point-of-care platform for sensitive, multiplexed, and affordable detection of allergen-specific IgE (sIgE) is an urgent demand in component-resolved diagnostics. Here, we developed a microfluidic immunosensing platform based on a rolling circle amplification-assisted DNA dendrimer probe for sensitive detection of multiple sIgEs. The versatile multichannel microfluidic whole blood analytical device integrates cell filtration, recombinant antigen-modified magnetic enrichment, and DNA dendrimer probe-amplified signal transduction for portable on-chip analysis. Three sIgEs against common oyster allergens were simultaneously detected in blood samples by simple smartphone-based imaging without any pretreatment. The quantitative detection of multiple allergen-specific antibodies on the platform was achieved with limits of detection of less than 50 pg/mL, exhibiting superior sensitivity compared to most point-of-care testing. The detection results of 55 serum samples and 4 whole blood samples were 100% consistent with the ELISA results, confirming the accuracy and stability of our platform. Additionally, the reversible combination of hexahistidine6-tag and Ni-IMAC magbead was elegantly utilized on the immunosensing platform for desired reversibility. With the advantages of general applicability, high sensitivity, and reversibility, the DNA dendrimer-based microfluidic immunosensing platform provides great potential for the portable detection of immune proteins as a point-of-care platform in disease diagnostics and biological analysis.

Management of food allergy based on oral food challenge.

Food allergy is a growing health problem that affects both patients and society in multiple ways. Despite the emergence of novel diagnostic tools, such as component-resolved diagnostics (CRD) and basophil activation tests (BAT), oral food challenge (OFC) still plays an indispensable role in the management of food allergies. This review aimed to highlight the indications and safety concerns of conducting an OFC and to provide insights into post-OFC management based on recent findings. Standardized OFC protocols have regional diversification, especially in Japan and Western countries. Recent studies suggested that the interval between doses should be at least more than an hour. Furthermore, applying a stepwise method tailored to the patient's specific immunoglobulin E level and history of anaphylaxis seems to mitigate these risks. Recent surveys have shown that, following a positive OFC, options other than strict avoidance are also selected. OFC serves diverse purposes, yet the risks it carries warrant caution. The stepwise protocol appears promising for its safety. Subthreshold consumption following OFC shows potential; however, further research on its efficacy and safety is required. Management following OFC should be tailored and well discussed between clinicians and patients.

Precision allergy molecular diagnosis applications in food allergy.

Precision medicine has become important in the diagnosis and management of food allergies. This review summarizes the latest information regarding molecular allergology, an essential component of food allergy managements. Component-resolved diagnostics (CRD) can be used to investigate sensitization to allergens based on symptoms and to reveal co-sensitization and/or cross-sensitization in patients with allergies. The following allergen components are known to be associated with symptoms: ovomucoid from eggs, omega-5 gliadin from wheat, and many storage proteins (Gly m 8 from soy, Ara h 2 from peanut, Cor a 14 from hazelnut, Ana o 3 from cashew nut, Jug r 1 from walnut, and Ses i 1 from sesame). Recent studies on allergens of macadamia nuts (Mac i 1 and Mac i 2), almonds (Pru du 6), fish (parvalbumin and collagen), and shrimp (Pem m 1 and Pem m 14) have provided additional information regarding CRD. In addition, Pru p 7 is a risk factor for systemic reactions to peaches and has recently been found to cross-react with cypress and Japanese cedar pollen. CRD provides information of individualized sensitization profiles related to symptoms and severity of allergies in patients. Clinical practice based on CRD offers many benefits, such as higher diagnostic accuracy and improved management of individual patients.

Component-specific clusters for diagnosis and prediction of allergic airway diseases.

Previous studies which applied machine learning on multiplex component-resolved diagnostics arrays identified clusters of allergen components which are biologically plausible and reflect the sources of allergenic proteins and their structural homogeneity. Sensitization to different clusters is associated with different clinical outcomes. To investigate whether within different allergen component sensitization clusters, the internal within-cluster sensitization structure, including the number of c-sIgE responses and their distinct patterns, alters the risk of clinical expression of symptoms. In a previous analysis in a population-based birth cohort, by clustering component-specific (c-s)IgEs, we derived allergen component clusters from infancy to adolescence. In the current analysis, we defined each subject's within-cluster sensitization structure which captured the total number of c-sIgE responses in each cluster and intra-cluster sensitization patterns. Associations between within-cluster sensitization patterns and clinical outcomes (asthma and rhinitis) in early-school age and adolescence were examined using logistic regression and binomial generalized additive models. Intra-cluster sensitization patterns revealed specific associations with asthma and rhinitis (both contemporaneously and longitudinally) that were previously unseen using binary sensitization to clusters. A more detailed description of the subjects' within-cluster c-sIgE responses in terms of the number of positive c-sIgEs and unique sensitization patterns added new information relevant to allergic diseases, both for diagnostic and prognostic purposes. For example, the increase in the number of within-cluster positive c-sIgEs at age 5 years was correlated with the increase in prevalence of asthma at ages 5 and 16 years, with the correlations being stronger in the prediction context (e.g. for the largest 'Broad' component cluster, contemporaneous: r = .28, p = .012; r = .22, p = .043; longitudinal: r = .36, p = .004; r = .27, p = .04). Among sensitized individuals, a more detailed description of within-cluster c-sIgE responses in terms of the number of positive c-sIgE responses and distinct sensitization patterns, adds potentially important information relevant to allergic diseases.

Dermatophagoides pteronyssinus proteins and their role in the diagnostics and management of house dust mite allergy: exploring allergenic components.

Component-resolved diagnostics enables the detection of allergen-specific immunoglobulins E (asIgE) to house dust mite (HDM) proteins, which may help clinicians to face the difficulties in diagnostics of HDM allergy. Currently, almost 40 proteins of Dermatophagoides species, that are able to bind asIgE, have been identified, and this number will certainly increase. The association between sensitisation to particular molecules and allergy symptoms is extensively studied. This investigation enables us to identify HDM molecules that promote respiratory, skin, or food allergies, and it could help us predict the possible course of allergic diseases. The individual repertoire of asIgE improves our understanding of immunological response, which underlies allergy symptoms, and helps to form individual therapeutic regimens. This review provides clinicians with information on Dermatophagoides pteronyssinus proteins available in commercial arrays, and their role in the diagnostics and management of HDM allergy.

Use of in vitro and in vivo tests in the diagnosis of food-induced anaphylaxis – a case study

Food allergy is a chronic disease that affects both children and adults. Systemic allergic reactions in children are most commonly caused by foods, especially nuts, milk, and eggs. A conventional diagnostic work-up for allergy typically pinpoints the allergen source, while component-resolved diagnostics is an approach that identifies the allergen molecules responsible for causing anaphylaxis. In some cases, determining the causative agent of anaphylaxis requires the use of various diagnostic tests. In the following paper, we want to highlight the importance of a critical approach to allergy tests results and caution in the diagnosis of idiopathic anaphylaxis. Based on a case report of food-induced anaphylaxis, we discuss the diagnostic methods that can be applied following a negative IgE test result for allergens obtained with a multiplex platform.

Peanut Allergy and Component-Resolved Diagnostics Possibilities-What Are the Benefits?

Peanut allergy is a widespread and potentially life-threatening condition that affects both children and adults, with a growing incidence worldwide. It is estimated to affect around 1-2% of the population in several developed countries. Component-resolved diagnostics is a modern approach to allergy diagnosis that focuses on identifying specific allergenic proteins to provide precise diagnoses and personalized treatment plans. It is a technique that enables the analysis of specific IgE antibodies against tightly defined molecules (components) that constitute the allergen. Component-resolved diagnostics is particularly valuable in peanut allergy diagnosis, helping to determine allergen components associated with severe reactions. It also aids in predicting the course of the allergy and enables the development of personalized immunotherapy plans; however, the full application of it for these purposes still requires more precise studies. In this paper, we present the current knowledge about peanut allergy and component-resolved diagnostics possibilities. We discuss the possibilities of using molecular diagnostics in the diagnosis of peanut allergy. We focus on examining and predicting the development of peanut allergy, including the risk of anaphylaxis, and describe the latest data related to desensitization to peanuts.

Potential and limitations of epitope mapping and molecular targeting in Hymenoptera venom allergy.

Hymenoptera venom (HV) allergy can lead to life threatening conditions by specific IgE (sIgE)-mediated anaphylactic reactions. The knowledge about major allergens from venom of different clinically relevant species increased in the last decades, allowing the development of component-resolved diagnostics in which sIgE to single allergens is analysed. Despite these advances, the precise regions of the allergens that bind to IgE are only known for few HV allergens. The detailed characterization of IgE epitopes may provide valuable information to improve immunodiagnostic tests and to develop new therapeutic strategies using allergen-derived peptides or other targeted approaches. Epitope-resolved analysis is challenging, since the identification of conformational epitopes present in many allergens demands complex technologies for molecular analyses. Furthermore, functional analysis of the epitopeś interaction with their respective ligands is needed to distinguish epitopes that can activate the allergic immune response, from those that are recognized by irrelevant antibodies or T cell receptors from non-effector cells. In this review, we focus on the use of mapping and molecular targeting approaches for characterization of the epitopes of the major venom allergens of clinically relevant Hymenoptera species. The screening of the most relevant allergen peptides by epitope mapping could be helpful for the development of molecules that target major and immunodominant epitopes blocking the allergen induced cellular reactions as novel approach for the treatment of HV allergy.

Environmental exposure and sensitization patterns in a Swiss alpine pediatric cohort

BackgroundThe level of environmental exposure throughout life may contribute to the prevalence of allergic sensitization and allergic disease. The alpine climate has been considered a healthy climate with little allergen exposure and pollution. We conducted a cross-sectional study to investigate local environmental exposure and concomitant prevalence of allergic sensitization among local school children born and raised in an alpine environment. MethodsClinical and demographic data were collected with a questionnaire. Allergen content was assessed in residential settled dust samples, lifetime exposure to pollen and air pollution was calculated using data from national pollen and air pollution monitoring stations, and the allergic sensitization profile was determined with component resolved diagnostics (ISAC®). Univariate and multivariate regression models were used to estimate the relation between exposure and sensitization. ResultsIn a cohort of children born and raised in an alpine environment, sensitization to aeroallergens is quite common (38%), especially to grass (33%) and cat (16%). House dust mite allergen was detected in up to 38% of residential dust samples, but sensitization to HDM was low (2.5%). Pollutant levels were low, but an increasing trend was observed in the amount of ozone and PM10. Living close to a busy road was associated with increased odds OR (95% CI) for being sensitized to any allergen 2.7 (1.0–7.2), to outdoor allergens 2.8 (1.1–7.1) and being sensitized plus reporting symptoms of rhinoconjunctivitis 4.4 (1.3–14.8) and asthma 5.5 (1.4–21). Indoor living conditions, including the presence of visible mold, increased the odds of being sensitized to indoor allergens (1.9 (1.1–3.2) and being sensitized plus reporting symptoms of rhinoconjunctivitis 1.9 (1.0–3.6) and asthma 2.1 (1.0–4.1). ConclusionIn a healthy alpine environment, pollution might still be an important factor contributing to allergic sensitization.

Basophil activation test (BAT) in double-sensitized patients with Hymenoptera venom allergy: additional benefit of component-resolved diagnostics.

In Hymenoptera venom allergy serologically double-sensitized patients it is often difficult to identify the culprit insect for venom immunotherapy (VIT). To evaluate if basophil activation tests (BATs) performed not only with venom extracts but additionally with single component-resolved diagnostics could differentiate between sensitized and allergic individuals and how the test results influenced the physicians' decision regarding VIT. BATs were performed with bee and wasp venom extracts and with single components (Api m 1, Api m 10, Ves v 1, Ves v 5) in 31 serologically double-sensitized patients. In 28 finally included individuals 9 BATs were positive and 4 negative for both venoms. 14/28 BATs showed positive results for wasp venom alone. 2/10 BATs positive for bee venom were only positive to Api m 1 and 1/28 BAT only to Api m 10, but not for whole bee venom extract. 5/23 BATs positive for wasp venom were only positive for Ves v 5, but negative for wasp venom extract and Ves v 1. Finally, VIT with both insect venoms was recommended in 4/28 individuals, with wasp venom alone in 21/28 patients and with bee venom alone in 1/28. In 2 cases no VIT was recommended. BATs with Ves v 5, followed by Api m 1 and Api m 10, were helpful for the decision for VIT with the clinically relevant insect in 8/28 (28.6%) patients. A BAT with components should therefore be additionally carried out in cases with equivocal results.