sIgE Detection Research Articles

B-059 Development and Validation of Multiplex Quantitative Allergy Tests based on Automated Flow Fluorescence Immunoassay Analyzer

Abstract Background Serological allergy tests measuring allergen-specific IgE (sIgE) are simpler and safer than skin prick tests, and the results are not influenced by skin condition or human factors. Quantitative detection of sIgE can also aid in evaluating patient allergies and aiding subsequent treatment. Dymind has researched and developed novel quantitative allergy tests based on the automated flow fluorescence immunoassay analyzer system (MF1280), enabling quantitative detection of multiple sIgE in just one test with one sample. Here, we present the performance of tIgE and two specific IgE test kits using the Dymind MF1280 system. Methods This study evaluated the performance of total IgE (tIgE) and two allergen-specific IgE (sIgE) panels of inhalant and food allergens, inhalant allergen panel including d1 (Dermatophagoides pteronyssinus), d2 (Dermatophagoides farina), i6 (Cockroach), e1 (Cat epithelium), e5 (Dog epithelium), w1(Common ragweed), and food allergen panel including f1 (Egg white), f2 (Cow’s milk), f3 (cod), f23 (Crab), 24 (Shrimp), and f27 (beef). Evaluation criteria included precision, linearity, limit of detection (LOD) and method comparison. As clinical performance of 425 clinical samples collected from 2 hospital laboratory in China was evaluated by both of Dymind allergen IgE MF1280 system and Phadia ImmunoCAP. Results The validated linearity of total IgE and sIgE were 2.0-5000.0 IU/mL and 0.1-100.0 IU/mL respectively. The LOD of total IgE and sIgE determined to be 2 IU/mL and 0.1 IU/mL respectively. The precision was evaluated by assaying a low and a high samples of every sIgE assay and the result of d1, d2, i6, e1, e5, w1, f1, f2, f3, f23, f24, f27 were 3.73% / 1.34% (low sample / high sample), 3.26% / 1.95%, 2.18% / 0.87%, 1.31% / 1.40%, 3.63% / 1.13%, 2.84% / 4.76%, 4.50% / 1.53%, 5.97% / 1.64%, 3.46% / 1.11%, 1.58% / 1.73%, 3.77% / 1.28%, 1.78% / 0.96% respectively. The total mean coefficient of measurements was below 7% to ensure high precision in multiplex quantitative analysis. Method comparison of 425 clinical samples between Phadia ImmunoCAP and Dymind allergen IgE showed total concordance rate was over 85% except f2 (over 80%). Conclusions The Dymind Allergen-specific IgE test kits on the automated flow fluorescence immunoassay analyzer system provide fast and accurate in vitro diagnostic detection of tIgE and sIgE for aiding diagnostics specific allergens sensitization and treatment for allergy patients, with good precision and excellent agreement compared to ImmunoCAP. The MF1280 system has advantages including random access, fully automated, multiplex quantitative detection of allergen sIgE with reducing assay time, sample consumption and lower costs.

Analysis of the effectiveness of cross-reactive carbohydrate antigen determinant antibody adsorbents in identifying allergen-specific IgE antibodies

This study aimed to investigate the influence of anti-cross-reactive carbohydrate determinant IgE antibodies (anti-CCD IgE) on the detection of allergen-specific IgE (sIgE) antibodies, as well as the application value of anti-CCD IgE adsorbents in detecting allergen sIgE. In this cross-sectional study, a total of 2 636 test samples from patients who received treatment in West China Hospital of Sichuan University and tested allergen sIgE using the western blot method from October 2020 to May 2021 were analyzed. In these samples, 709 samples tested postive of allergen sIgE. 46 stochastic venous serum samples that tested positive in both sIgE and anti-CCD IgE and 1 serum sample that tested positive in sIgE but negative in anti-CCD IgE were collected. These samples were processed by anti-CCD IgE adsorbents, followed by allergen sIgE detection. The difference between the two detection results before and after adsorption was analyzed. The allergen test results showed that the positive rate of anti-CCD IgE in samples was 2.6% (69/2 636) during the period of sample collection. After treatment with anti-CCD IgE adsorbents, the top three allergen-sIgE of the positive rate changed from tree combination 2 (willow/poplar/elm), common ragweed and peanut to dust mite combination, cockroach and crab. The positive anti-CCD IgE results of 46 samples all turned negative and the total positive sIgE antibody dropped by 62.8%; the positive rate of sIgE antibodies with the class result ≥2 significantly decreased after treatment with anti-CCD IgE adsorbents, especially the positive rate of common ragweed dropped by 96.2%. The results of positive samples showed that multiple sIgE antibodies declined by different ranges, involving up to 11 antibodies with a maximum decline of 4 classes. Strongly positive sIgE antibodies (the class result ≥4) also had a high conversion rate of negative (25.0%-100%). The positive sIgE antibodies in about 60% of the samples decreased by more than 2, and the sIgE antibodies in 17.4% of the samples turned completely negative. There was no change in the allergen sIgE detection results of the sample with negative anti-CCD IgE after treatment. In conclusion, sIgE antibodies including targeting common ragweed, humulus, tree combination 2 (willow/poplar/elm), etc. are susceptible to false positives caused by anti-CCD IgE. Treatment of samples with anti-CCD IgE adsorbents can significantly reduce the risk of false positives caused by anti-CCD IgE. It is necessary to pretreat samples that were anti-CCD IgE positive with anti-CCD IgE adsorbents, which can make laboratory results more accurate and provide a reference for diagnosis and prevention of allergic diseases.

Mapping of IgE cross-reactivity of Gly m 4, Gly m 5 and Gly m 6 soybean allergens in patients with atopic diseases

Currently, a significant portion of the food consists of multiple different ingredients. Soybean proteins have been widely used for production of these combined foodstuffs. Meanwhile, soy proteins may contain a wide range of allergens, and even, if present in small amounts, they can cause severe allergic reactions due to cross-reactivity. The aims of our study were to evaluate the prevalence of sensitization to soybean allergen components Gly m 4, Gly m 5 and Gly m 6, and to map their IgE cross-reactivity with homologous proteins of Bet v1-like proteins and cupin proteins in patients with atopic disorders. We have studied IgE’s to 112 allergenic components of plant and animal origin in blood sera from 54 patients with history of allergy, using the ImmunoCap ISAC method. The results were analyzed by means of MS Excel program using parametric statistical criteria. Results: In patients with atopic diseases, we have detected serum IgE to the rGly m 4 allergic component (5 patients out of 29; 17.24%). Frequency of sIgE detection to rGly m 5 (3 patients of 29; 10.24%) and rGly m 6 (1 patient of 29; 3.44%) was less pronounced. Cross-reactive sIgE was detected only to allergens of the Bet v1 superfamily. The strongest relationship was found between sIgE level to rGly m 4 and rBet v1 (R = 0.68; p = 0.001). Another IgE cross-reaction was found between soybean rGly m 4 and alder pollen rAln g1 (R = 0.681; p = 0.000). IgE antibodies to rGly m 4 may also cross-react with kiwi rAct d8 (R = 0.59; p = 0.001). We have also found a weak correlation between sIgE to soybean rGly m 4 and two hazelnut rCor a1 isoforms: rCor a 1.01 (R = 0.42; p = 0.023), and rCor a 1.04 (R = 0.39; p = 0.036). The IgE cross-reactivity profile of the soy allergens revealed in this study is important for improvement of testing strategy for the presence of causally significant allergens. This finding will help to avoid the development of hidden cross-reactions that trigger both oral and respiratory allergic processes in subjects with allergic pathology. Moreover, this will enable administration of optimal diets and develop technologies for development of hypoallergenic food products.

Allergen Microarrays and New Physical Approaches to More Sensitive and Specific Detection of Allergen-Specific Antibodies.

The prevalence of allergic diseases has increased tremendously in recent decades, which can be attributed to growing exposure to environmental triggers, changes in dietary habits, comorbidity, and the increased use of medications. In this context, the multiplexed diagnosis of sensitization to various allergens and the monitoring of the effectiveness of treatments for allergic diseases become particularly urgent issues. The detection of allergen-specific antibodies, in particular, sIgE and sIgG, is a modern alternative to skin tests due to the safety and efficiency of this method. The use of allergen microarrays to detect tens to hundreds of allergen-specific antibodies in less than 0.1 mL of blood serum enables the transition to a deeply personalized approach in the diagnosis of these diseases while reducing the invasiveness and increasing the informativeness of analysis. This review discusses the technological approaches underlying the development of allergen microarrays and other protein microarrays, including the methods of selection of the microarray substrates and matrices for protein molecule immobilization, the obtainment of allergens, and the use of different types of optical labels for increasing the sensitivity and specificity of the detection of allergen-specific antibodies.

Detection of Specific IgE against Molds Involved in Allergic Bronchopulmonary Mycoses in Patients with Cystic Fibrosis.

Allergic bronchopulmonary mycoses (ABPM) can be due to molds other than Aspergillus fumigatus in patients with cystic fibrosis (pwCF). We aimed to develop immunoassays for the detection of specific IgE (sIgE) directed against five fungal species involved in ABPM: Aspergillus terreus, Scedosporium apiospermum, Lomentospora prolificans, Rasamsonia argillacea, and Exophiala dermatitidis. Serum samples (n = 356) from 238 pwCF, collected in eight CF care centers in France, Germany, and Italy, were analyzed by dissociated enhanced lanthanide fluorescent immunoassay (DELFIA®) to assess levels of sIgE directed against antigenic extracts of each fungus. Clinical, biological, and radiological data were collected for each episode. One hundred serum samples from healthy blood donors were used as controls. Sera were classified into four groups depending on the level of sIgE according to the quartile repartition calculated for the pwCF population. A score of 4 for values above the 3rd quartile corresponds to an elevated level of sIgE. PwCF showed higher levels of sIgE than controls. Based on criteria from the ABPA-ISHAM working group, with an additional criterion of "a sIgE score of 4 for at least one non-A. fumigatus mold", we were able to diagnose six cases of ABPM. Using 417IU/mL as the threshold for total IgE and the same additional criterion, we identified seven additional pwCF with "putative ABPM". Detection of sIgE by DELFIA® showed good analytical performance and supports the role played by non-A. fumigatus molds in ABPM. However, commercially available kits usable in routine practice are needed to improve the diagnosis of ABPM.

Evaluation of the clinical performance of multiple serum sIgE detection systems based on component-resolved diagnosis.

Serum allergen-specific IgE (sIgE) detection is an important tool in the diagnosis of allergic diseases. However, the absence of international standards for sIgE detection systems raises questions about the comparability of different systems. This study aims to evaluate three common allergen sIgE detection systems, with a primary focus on detecting dust mite allergens. We recruited 85 children with rhinitis and 15 healthy control children. The subjects underwent testing with three different sIgE detection systems, including magnetic particle flow fluorescence, magnetic particle chemiluminescence, and protein chip, to detect sIgE levels to HDM extracts. In addition, skin prick testing (SPT) was conducted, and protein chip technology was performed to measure sIgE levels to component proteins. Our findings reveal strong consistency between SPT and the three in vitro detection systems, with consistency exceeding 71.76% for dust mite allergens. Moreover, there was excellent consistency and RAST class consistency among the three in vitro detection systems, with scores exceeding 94.12% and 89.00%, respectively. And for the 13 additional allergens crude extracts sIgE simultaneously detected by systems 1 and 2, the results showed that the consistency of both systems was above 87.00%, and the RAST class consistency was above 82.00%. The three serum sIgE detection systems exhibited an approximate 80% concordance rate with SPT in identifying dust mite allergens. Furthermore, these systems demonstrated excellent consistency and RAST class consistency among themselves. These findings suggest that the three assays introduced in this study are interchangeable in allergen diagnosis.

Molecular diagnostic strategies and management of dust mite allergy

Dust mites are one of the most important allergens, widely distributed around the world, especially in household environments. Dermatophagoides pteronyssinus, Dermatophagoides farinae and Blomia tropicalis are the most common species of dust mites. There are more than 35 known sensitization components of dust mites, among which Der p 1, Der p 2 and Der p 23 are the major components. Clinically, allergen skin test and serum specific immunoglobulin E (sIgE) detection are widely used in the preliminary diagnosis of dust mite allergy. However, these methods cannot accurately identify specific dust mite sensitization components. Considering that there are significant differences in the allergenic components of dust mites in different regions and populations, component-resolved diagnosis of dust mite is particularly important in accurately determining the allergenic components. This is not only of guiding significance for allergen avoidance, but also important for determining the immunotherapy regimen for dust mites. In order to strengthen the understanding of the molecular diagnosis of dust mites and promote the integration of allergy science in China with the international standards, this article interprets the "Allergy Molecular Allergology User's Guide 2.0" published recently by the European Academy of Allergy and Clinical Immunology.

Impact of ultra-low temperature storage on serum sIgE detection and allergic disease biobank feasibility

Research has shown that the concentration and composition of biological samples may change after long-term ultra-low temperature storage. Consequently, this study examined the effect of ultra-low temperature storage on serum sIgE detection by comparing sIgE concentrations at various durations from the time of sample storage to subsequent testing. We selected 40 serum samples from the Guangzhou Medical University Affiliated First Hospital Biobank, which had been tested for house dust mites, dog hair, tobacco mold, cockroaches, and cow milk allergen sIgE. Samples were categorized by storage duration: 14 samples stored for 10 years, 12 for 5 years, and 14 for 3 years. They were also classified by sIgE positive levels: 15 samples at levels 1–2, 15 at levels 3–4, and 10 at levels 5–6. The allergen sIgE of these samples was retested using the same technology. Regardless of the type of allergen or the level of positivity, the majority of sIgE concentrations measured at the time of storage were higher than the current measurements, but the difference was not statistically significant. The correlation between the sIgE results at the time of storage and the current results was high for samples stored for 10 years (rs = 0.991, P < 0.001) and 5 years (rs = 0.964, P < 0.001). Serum allergen sIgE is stable when stored under ultra-low temperature conditions, making the construction of a biological sample bank for allergic diseases feasible. This will facilitate researchers in quickly obtaining samples, conducting technical research, and translating findings, thereby promoting the development of the field of allergy through integration of industry, academia, and research.

Glutamine and lysine as common residues from epitopes on α-lactalbumin and β-lactoglobulin from cow milk identified by phage display technology

Cow milk is an important source of food protein for children; however, it could lead to allergy, especially for infants. α-Lactalbumin (α-LA) and β-lactoglobulin (β-LG) from whey protein make up a relatively high proportion of milk proteins and have received widespread attention as major allergens in milk. However, few studies have identified the epitopes of both proteins simultaneously. In this study, ImmunoCAP and indirect ELISA were first used for detection of sIgE to screen sera from allergic patients with high binding capacity for α-LA and β-LG. Subsequently, the mimotopes was biopanned by phage display technology and bioinformatics and 17 mimic peptide sequences were obtained. Aligned with the sequences of α-LA or β-LG, we identified one linear epitope on α-LA at AA 11-26 and 5 linear epitopes on β-LG at AA 9-29, AA 45-57, AA 77-80, AA 98-101, and AA 121-135, respectively. Meanwhile, the 8 conformational epitopes and their distributions of α-LA and β-LG were located using the Pepitope Server. Finally, glutamine and lysine were determined as common AA residues for the conformational epitopes both on α-LA and β-LG. Moreover, we found the addition of mouse anti-human IgE during the biopanning process did not significantly affect the identification of the epitopes.

Paper-based microfluidics and tailored gold nanoparticles for visual colorimetric detection of multiplex allergens

The highly efficient and accurate recognition of targeted allergens is an essential element in the diagnosis of allergic diseases and follow-up desensitization treatment in clinic. The current clinical methods widely used to detect sIgE are high cost, time-consuming procedures, and bulky equipment. Herein, a multiplex microfluidic paper-based device (multi-μPAD) was developed that combined with tailored gold nanoparticles for simultaneously visual, colorimetric detection of different allergens in serum. This device could be used as quantitative detection of sIgE with LOD as low as 0.246 KUA/L in colorimetric method. In vitro results also showed that this device possessed good repeatability, high accuracy and incredible stability in different pH (6.0–7.4) and temperature (24–37 °C), as well as long-term storage within 90-day. Finally, this method was successfully utilized for assessing clinical multi-sample screening in 35 allergic patients. After the addition of the samples from allergic patients, the agreement rate of clinical results with commercial enzyme-linked immunosorbent assay (ELISA) kit reached more than 97%, which further indicated that this device had the advantages of efficient, accurate and sensitive to screen various allergens in real clinical serum samples. Therefore, by simply altering antigens and antibodies, this device can also be used for high-throughput detection of other allergens, making it considerable potential for clinical diagnosis of allergic diseases.

Ni-NTA resin-based multiplexed origami device for highly efficient sensing of allergen-specific IgE

Food allergy diagnosis requires a highly sensitive detection of allergen-specific immunoglobulin E (sIgE) in the serum. Enzyme-linked immunosorbent assay (ELISA) is a classical method widely used for sIgE detection but had to rely on costly and time-consuming assay procedures, skilled technicians, and bulky equipment. Here, a multiplexed origami paper analytical device (moPAD) that is hexahistidine-tagged and integrated with a nitrilotriacetic acid-functionalized surface with nickel (Ni-NTA) was developed to achieve low-cost and high-efficiency immunosensing of multiple allergen-specific IgEs in serum. The major oyster allergens, Cra a 1, Cra a 2, and Cra a 4, were used to detect sIgE in human serum. The feasibility of the moPAD-based immunosensing strategy was successfully demonstrated by desirable sensitivities for multiple targets. The detection results of moPAD for 72 serum samples were 100% consistent with clinical test results, while 69 of these results showed no significant differences from ELISA results, demonstrating the accuracy and stability of this method. A fully integrated moPAD reduces detection time and achieves highly sensitive quantification using a simple smartphone-based readout. Efficient allergen modification of paper devices has great applicability in allergen component-resolved diagnostics. The implementation of moPAD can make the process of allergy diagnosis simpler for patients, physicians, and healthcare systems alike.

Analysis of specific sIgE detection of house dust mites and aspergillus fumigatus in 2 535 patients with respiratory allergic diseases and respiratory infectious diseases in the Guangzhou area

Objective: To compare the specific IgE positive rates of the patients between allergic respiratory diseases and respiratory infectious diseases in Guangzhou, the relationship between the co-sensitization of house dust mite (HDM) allergen and Aspergillus fumigatus (AF) allergen and asthma, allergic rhinitis with asthma, pneumonia, upper respiratory infections, bronchitis, serum total immunoglobulin E (total Immunoglobulin E, tIgE) and age were analyzed, to provide the basis for the prevention and treatment of respiratory allergic diseases and respiratory infectious diseases in this area. Methods: A total of 2 535 patients with confirmed respiratory allergic diseases and respiratory infectious diseases were selected retrospectively from the outpatient or inpatient department of the First Affiliated Hospital of Guangzhou Medical University from April 2017 to June 2021 and detected HDM and AF specific IgE (sIgE) by the ImmunoCAP system. The age range was 1 to 89 years. The median age was 5 years. The average age was 9. ≤3 years old group n=894, 4-6 years old group n=721, 7-18 years old group n=615, 19-49 years old group n=207, >49 years old group n=98. There were 1 596 males (62.96%) and 939 females (37.04%). There were 1 279 cases of allergic diseases and 1 256 cases of respiratory infectious diseases. The different disease groups were divided into asthma group (411 cases), allergic rhinitis group (458 cases), allergic rhinitis combined with asthma group (410 cases), pneumonia group (463 cases), upper respiratory tract infection group (299 cases) and bronchitis group (494 cases). The difference of specific IgE (sIgE) and tIgE between HDM and AF was analyzed. For statistical analysis, continuous variables were tested by Mann-Whitney U. Classification data by chi-square test or Fisher's exact test. Results: 1 313 (51.79%) patients were sIgE positive for HDM allergen, 65 (2.56%) were sIgE positive for AF allergen, and 50 (1.97%) were both positive. In the respiratory allergic disease group, 877 cases (68.57%,877/1 279) were positive for HDM allergen sIgE, 57 cases (4.46%,57/1 279) were positive for AF allergen sIgE, and 44 cases (3.44%,44/1 279) were both positive; 436 cases (34.71%,436/1 256) of respiratory infectious diseases were positive for HDM allergen sIgE, 8 cases (0.64%,8/1 256) were positive for AF allergen sIgE, and 6 cases (0.48%,6/1 256) were both positive. In monosensitization, the HDM allergen sIgE sensitization rate was the highest in the allergic rhinitis & asthma group, at 80.24% (329/410). The positive rate of HDM allergen sIgE in male patients was 53.76%(858/1 596), and the positive rate in female patients was 46.22%(434/939), and the difference between the two was statistically significant (χ2=13.449, P<0.001). In polysensitization, asthma patients (5.35%,22/411) had the highest positive rate of HDM sensitization with AF, followed by allergic rhinitis patients (3.06%,14/458), allergic rhinitis with asthma (1.95%,8/410). The positive rate of respiratory infectious diseases such as pneumonia (0.43%,2/463), upper respiratory infections (0.33%,1/299), and bronchitis (0.61%,3/494) with AF was extremely low. The positive rate of HDM combined with AF in infants(≤3 years old group,0.34%, 3/894; 4-6 years old group, 0.97%, 7/721)was significantly lower than that in teenagers and adults(7-18 years old group,3.58%, 22/615; 19-49 years old group,6.28%, 13/207;>49 years old group,5.10%, 5/98).In the patients with HDM and AF combined sensitization, HDM sIgE levels were distributed in all grades, and AF sIgE levels were mainly in grades 1, 2, and 3. Conclusion: The positive rate of HDM combined with AF was higher in patients with respiratory allergic diseases such as asthma, allergic rhinitis, and allergic rhinitis combined with asthma, suggesting that clinical attention should be paid to the combination of HDM and AF in patients with asthma and allergic rhinitis, especially adults, more likely to be combined with AF.

Allergens sensitization among children with allergic diseases in Shanghai, China: age and sex difference

BackgroundThe distribution of allergens has geographic characteristics. Local epidemiological data provides evidence-based strategies for the prevention and management of allergic diseases. Age and sex differences may exist in the prevalence of sensitivity to various allergens. We investigated the distribution of common allergens in allergic children in Shanghai, southeastern China.Methods39,926 children 1 month to 18 years of age diagnosed with allergic diseases were tested for the presence of serum-specific Immunoglobulins E (sIgE) to 17 allergens common to this region, using a reversed enzyme allergosorbent test.Results25,757 (64.5%) of the subjects showed elevated sIgE to at least one of the tested allergens. House mite and dust mite were the most common aeroallergens, while egg and milk were the most common food allergens. The most common aeroallergens and food allergens were similar among each allergic disease. By age-group analysis, the positive rates of aeroallergens were higher at older age. Several peaks of sensitization to food allergens were observed in children between 1 and 3 years of age for eggs, milk, nut, crab and shrimp. In addition, the sensitization to beef and mango was highest in children 3–6 years of age. The rate of positive sIgE detection was higher in males than females for all the tested allergens except cockroach, trees and beef. Considering the interplay between sex and ages and other related components (including season, monthly temperature, humidity, air quality index, test rate of patients), the sIgE positive rates of the main aeroallergens increased with age, while the main food allergens decreased; males are more sensitive to several aeroallergens (including dust mite, house mite, cat epithelium, dog epithelium and mulberry).ConclusionsHouse mite, dust mite, milk, and egg are major allergens in Shanghai. Children at younger age are more sensitive to food allergens, while increasing overall prevalence of sensitization can be found with increasing age. Boys have higher positive rates of sIgE responses than girls. Knowledge of the prevalence of allergen sensitization in different age groups and sex may help facilitate diagnosis and intervention efforts to mitigate the impact of allergic diseases in this large geographical region. This approach may be extrapolated to other regions.

Hexamerin-2 Protein of Locust as a Novel Allergen in Occupational Allergy.

BackgroundOccupational exposure to locusts induces a high prevalence of allergic sensitization. However, knowledge on occupational locust allergens remains unclear.ObjectiveThis study aimed to identify the allergens from locusts causing occupational allergies.MethodsWe conducted a survey of 57 persons exposed to locusts using questionnaires and immunological tests for occupational allergies in long-term locust laboratories. The major allergen was identified by immunoblotting and analysed by mass spectrometry. The allergenicity of the allergen was assessed by sIgE detection, immunoblotting and ELISA inhibition assays.ResultsThe survey indicated that the frequency of locust occupational allergies was 40.4% among subjects exposed to locust. The symptoms in most males were allergic rhinitis, while females showed higher prevalence of atopic dermatitis. Occupational exposure increased the allergy risk. The recombinant hexamerin-2 protein possesses high allergenicity in the allergic exposure group. Hexamerin-2 protein can inhibit IgE reactivity with locust protein extracts by approximately 60%. The potential for cross-reactivity with cockroaches was indicated by sequence alignment of hexamerin-2 protein and allergens of cockroaches.ConclusionThe hexamerin-2 protein of locusts as an important allergen was identified. Therefore, occupational exposure is an important risk factor for locust allergy.

Nasal lavage fluid sIgE levels in differential diagnostics of allergic rhinitis.

Differential diagnosis plays a key role in diagnosing specific types of allergic rhinitis. The method involving allergen-specific immunoglobulin E (sIgE) detection in nasal lavage fluid, which has continually been the object of standardization efforts, is characterized by high specificity/sensitivity and plays a special role in diagnosing local allergic rhinitis. This article is a systematic review of the literature on the methodology, standardization, and use of sIgE detection in nasal lavage fluid in patients undergoing diagnostic tests for allergic rhinitis.

Validation of a commercial allergen microarray platform for specific immunoglobulin E detection of respiratory and plant food allergens

BackgroundAs the use of multiplex-specific immunoglobulin E (sIgE) detection methods becomes increasingly widespread, proper comparative validation assessments of emerging new platforms are vital. ObjectiveTo evaluate the clinical and technical performance of a newly introduced microarray platform, Allergy Explorer (ALEX) (MacroArray Diagnostics), in the diagnosis of pollen (cypress, grass, olive), dust mite (Dermatophagoides pteronyssinus), mold (Alternaria alternata), fruit (apple, peach), and nut (walnut, hazelnut and peanut) allergies and to compare it with those of the ImmunoCAP Immuno Solid-phase Allergen Chip (ISAC) 112 microarray and the ImmunoCAP singleplex method (ThermoFisher Scientific). MethodsWe enrolled 153 patients with allergy and 16 controls without atopy. The sIgE assays were conducted using ISAC112, ALEX version 2 (ALEX2), and ImmunoCAP for whole extracts and major components. Technical validation of ALEX2 was performed by measuring repeatability and interassay, interbatch, and interlaboratory reproducibility. ResultsWhen measured globally (detection by 1 or more allergen components), ALEX2 had adequate sensitivity and specificity for most of the allergens studied, comparable in general with that of ISAC112 (except for olive pollen and walnut) and similar to that of ImmunoCAP whole extract measurements. Component-by-component analysis revealed comparable results for all techniques, except for Ole e 1 and Jug r 3, in both ISAC112 and ImmunoCAP comparisons, and Alt a 1, when compared with ISAC112. Continuous sIgE levels correlate with sIgE by ImmunoCAP. Good reproducibility and repeatability were observed for ALEX2. ConclusionALEX2 has sound technical performance and adequate diagnostic capacity, comparable in general with that of ISAC112 and ImmunoCAP.

Advances of allergen component detection in the prevention and control of allergic diseases

The incidence of allergic diseases in China is increasing year by year, which has caused heavy public health burden to individuals and society. The detection of specific IgE (sIgE) is an important way to diagnose the etiology of allergic disease. Currently, the diagnosis of allergic rhinitis In vitro mainly focus on the specific IgE of crude extracts in clinical practice, while the detection of sIgE in allergen components is rarely carried out. Clinicians, especially non-allergists, do not have sufficient understanding about the importance of sIgE in allergen component detection. Knowing the related types and clinical significance of allergen components can improve the diagnostic level of allergic diseases. Allergen component detection can distinguish the major components of common allergens, identify cross-sensitization, predict the risk of anaphylaxis, guide allergen immunotherapy and develop precise dietary regimens, so as to provide accurate prevention and control recommendations for patients.

Basophil activation test in the diagnostics of hymenoptera venom allergy.

The aim of the study was to analyse the diagnostic performance of the basophil activation test (BAT), to compare the diagnostic reliability of BATs performed with different types of allergens, which are available in Slovakia and to verify the correlation between the symptom severity and the sensitivity and specificity of the BAT in 114 patients with suspected hymenoptera venom allergy (HVA). Diagnosis of the HVA and the identification of the appropriate venom for immunotherapy are in Slovakia based on detailed patient'medical history, skin tests and detection of sIgE. In unclear cases, where the clinical decision regarding the relevant insect species for immunotherapy is difficult, the cellular tests are recommended in several countries, such as Sweden, Spain, Germany, Denmark and Italy. In Slovakia, BAT is not adapted as s part of routine diagnostic work-up. The identification of the culprit hymenoptera species among 114 patients was based on detailed history, skin tests and detection of sIgE. Obtained results were compared with the results acquired by the BAT. The sensitivity of the BAT was 80.8 % and the specificity was 87.8 %. The sensitivity of the BAT was higher when using Soluprick SQ Allergens, but the specificity was higher with BŰHLMANN CAST Allergens. In the study no correlation between the symptom severity and the sensitivity and specificity of the BAT was observed. The results show that the BAT can be recommended in the identification of the appropriate venom for immunotherapy, the only specific treatment that is currently available for patients with HVA. Allergen source is one of critical factors in diagnostic reliability of the BAT (Tab. 4, Ref. 29) Keywords: hymenoptera venom allergy, allergy diagnosis, basophil activation test, sensitivity, specificity.

Evaluation of the clinical performance of four fungus-specific immunoglobulin E detection systems in patients with Aspergillus allergy.

Allergic bronchopulmonary aspergillosis (ABPA) is an airway disease caused by Aspergillus (mainly Aspergillus fumigatus). To evaluate the diagnostic performance of four fungal-related allergen-specific immunoglobulin E (sIgE) detection systems. A total of 99 patients with ABPA and 30 control patients admitted to the First Affiliated Hospital of Guangzhou Medical University from 2017 to 2019 were included in the study. Four allergen detection systems were used to detect Aspergillus-related sIgE. The 99 patients were divided into two groups based on the total IgE. Fluorescence immunoassay for fungal mixtures detected positive rates of 100% and 81% in the Confirmed and Probable groups, respectively. For Aspergillus fumigatus, the positive rates were 90.2% and 87.9%, respectively. In the detection of sIgE of fungal mixtures in all ABPA patients, the sensitivity of System 1 was 90.9%, which was higher than for the other three systems (System 2, 38.4%; System 3, 44.4%; System 4, 52.5%), All four systems have excellent specificity ( > 90.0%) and had higher consistency in the Confirmed group than in the Probable group (P < 0.05). Consistency for the Aspergillus mixture and Aspergillus fumigatus detected by fluorescence immunoassay was 90.2% and 86.2% in the Confirmed and Probable groups, respectively. Despite the many methods used to detect fungal-related sIgE, the ImmunoCAP system has the best clinical diagnostic performance. It is recommended that this method be used to detect fungal (mixtures or Aspergillus fumigatus) sIgE in order to reduce the missed diagnosis rate of ABPA.

Evaluation of a fully automated and completely quantitative allergen-specific IgE and total IgE detection assay.

Based on the current urgent need for an in vitro quantitative detection system for allergens in most hospitals in China, we introduced a novel allergen-specific immunoglobulin E detection system that employs a solid phase enzyme-linked immunoassay and evaluated its clinical performance. The system uses a special reaction component (innovative patents) to reduce the reaction time to 12 min, achieving point-of-care testing for allergy management, which is impressive compared to the 3-18 h testing time for all other systems. In addition, the AILEX system has excellent consistency with the ImmunoCAP reference method system; therefore, we recommend the introduction of the AILEX system for clinical auxiliary diagnosis in medical units.