Comparison of Immunoglobulin E Measurements on IMMULITE and ImmunoCAP in Samples Consisting of Allergen-Specific Mouse-Human Chimeric Monoclonal Antibodies towards Allergen Extracts and Four Recombinant Allergens (original) (raw)

Allergen-Specific IgE Measurement: Intermethod Comparison of Two Assay Systems in Diagnosing Clinical Allergy

Journal of Clinical Laboratory Analysis, 2016

Background: Our aim was to examine the performance of IMMULITE 2000 assay for specific IgE (sIgE) by comparing it with ImmunoCAP technology in light of a clinical background. Methods: Measurements of sIgE were done in a selected patient group (N = 569; varied sample size for each allergen) and in a random sample group (N = 100; 8 allergens). sIgE results were correlated with skin-prick test results (selected patients) and medical history (nonselected patients). Results: We have detected fair to excellent correlation and agreement between the results of both assays, despite their methodological differences, both in selected and nonselected patient group (qc = 0.431-0.976; qc = 0.390-0.972, respectively). Associations of sIgE levels with skin-prick test (SPT) levels and medical history have shown significant correlation for both assays for majority of tested allergens, where applicable (D. pteronyssinus, cat dander, egg white, milk, peanut, orchard grass, Alternaria tenuis, and common ragweed in selected patients; birch, cat dander, common ragweed, D. pteronyssinus, and orchard grass in nonselected; P < 0.05 for all). Conclusions: Laboratory testing for sIgE can be successfully accomplished by IMMULITE 2000 immunoanalyzer at a diagnostic accuracy relative to SPT, comparable to the results acquired by CAP technology but not fully comparable on the level of an individual patient. J.

Monoclonal antibodies to three distinct epitopes on human IgE: Their use for determination of allergen-specific IgE

Journal of Immunological Methods, 1984

Three different monoclonal antibodies (MAb) against human immunoglobulin E have been obtained which specifically bind to human myeloma and polyclonal IgE. The antibodies showed high avidities for soluble IgE (0.7 × 109 to 3.3 × 109 M−1). These MAb defined three distinct epitopes on IgE. A mixture of these antibodies in combination with an 125I-labelled anti-mouse Kappa chain MAb has been used to measure allergen-specific IgE. This determination was performed by a solid-phase radioimmunoassay using allergen extracts coated to either chemically activated paper discs or to polyvinyl chloride wells. This method is 4–10 times more sensitive than other previously reported procedures. A similar technique has also been applied to detect individual allergens in immunoblots of allergen extracts.

Specific IgE density assay: A new reverse enzyme allergosorbent test-based procedure for the quantitative detection of allergen-specific IgE

Allergology International, 1999

A new method is described for the quantitative detection of IgE antibodies, based on IgE capture with a specific antibody, reaction with liquid-biotinylated allergens and biotinylated anti-IgE and immunoenzymatic development of the reaction (reverse enzyme allergosorbent test). Using a reference system based on the World Health Organization IgE International standard, this method determines total IgE in the range 2-100kU/L and specific IgE in the range 0.2-100 kU/L, from which the specific/total ratio, called 'specific IgE density', can be calculated. This procedure has been applied to the study of specific IgE in 23 sera from patients polysensitized to pollen and mite allergens: 11 with asthma and 12 with rhinitis. The sensitivity and reproducibility of the method were evaluted. Sera from asthmatic patients showed higher cumulative levels of specific IgE (mean density 57.7%) than sera from rhinitic patients (mean density 32.6%). The clinical significance of specific IgE density in patients with multiple sensitizations is discussed.

Quantitative IgE antibody assays in allergic diseases

Journal of Allergy and Clinical Immunology, 2000

During the past several years, immunoassays for specific IgE antibodies have been refined to permit reporting results in mass units. Thus quantitative immunoassays for IgE antibodies may be an adjunct to skin tests. In cases of food allergy among children with atopic dermatitis, cutoff values for IgE antibody concentrations to egg, milk, peanut, and fish have been derived to provide 95% positive and 90% negative predictive values. Food-specific IgE antibody determinations can also be used to predict which food allergies are resolving spontaneously. Elevated egg-specific IgE antibody levels in infancy are associated with significantly increased risk for development of inhalant allergies later in childhood. In cases of inhalant allergy, specific IgE antibody levels correlate closely with results of inhalation challenge studies in cat-sensitive persons. Also, mite-specific IgE antibody levels correlate significantly with the mite allergen contents of reservoir dust in the homes of mite-sensitive persons. Immunoassays for quantitation of specific IgE antibodies may be used to document aller-gen sensitization over time and to evaluate the risk of reaction on allergen exposure. However, immunoassays and skin tests are not entirely interchangeable, and neither will replace the other in appropriate circumstances. (J Allergy Clin Immunol 2000;105:1077-84.)

In vitro diagnosis of allergy: how to interpret IgE antibody results in clinical practice

Primary care respiratory journal : journal of the General Practice Airways Group, 2006

The basis of any diagnosis of allergy requires a good history and examination, which should then provide a certain degree of confidence as to whether or not allergy is present. However, the diagnosis cannot be confirmed on the basis of symptoms alone, because both allergic and non-allergic conditions can present with similar symptoms. Based on prevalence figures, about half of the patients presenting with allergic symptoms in primary care may be non-allergic. Therefore, allergy testing in the form of specific IgE (sIgE) measurement and/or skin prick testing is an invaluable aid in demonstrating both the presence and severity of such an allergy. The usefulness of such tests extends beyond just the positive or negative result. Often, more information can be gleaned by using the test results in a form of a continuous variable in order to determine the likelihood that allergy can be attributed as an explanation for patients' symptoms and disease. In this review, we describe the rati...

IgE antibody-specific activity in human allergic disease

Immunologic Research, 2010

IgE antibody concentration, affinity, clonality and specific activity (also known as the allergen-specific IgE to total IgE ratio) influence the translation of IgE responses into clinically evident allergic symptoms following allergen exposure. Reported IgE-specific activity levels [3-4% place allergic individuals undergoing anti-IgE (Omalizumab Ò ) therapy at a disadvantage for poor resolution of their allergy symptoms following manufacturer's recommended dosing schemes. We investigated the hypothesis that the specific activity of the IgE antibody response is highly variable with respect to age, allergen specificity and an individual's total serum IgE level. Second, we investigated whether the IgE-specific activity level influences the extent and rate of loss of effector cell mediator release. IgE-specific activity distributions were plotted against age, allergen specificity and total serum IgE using 18,950 paired total IgE and allergen-specific IgE antibody data obtained from the analysis of sera from 3,614 allergic subjects and covering 182 allergen specificities. The fraction of specific IgE antibody of the total serum IgE was dependent on age of the individual, epitope specificity (clonality) and total serum IgE. The youngest group of allergic individuals with the lowest total serum IgE levels tended to have the highest allergen-specific IgE to total IgE ratios. Hymenoptera venom (54%), peanut (33%) and milk (27%) were the three allergen specificities that elicited the highest frequency of IgE-specific activities [4% among sensitized individuals. A prospective double-blind, placebo-controlled clinical study involving anti-IgE treatment of cat-allergic subjects showed IgE-specific activity was remarkably constant over the 16-week course of treatment, despite the up to 8-fold rise in total serum IgE following repetitive Omalizumab Ò administration. Changes in specific and total IgE levels paralleled each other in patients receiving anti-IgE therapy. The fastest rate of reduction in cat allergen-induced basophil histamine release following anti-IgE therapy was observed when the cat-specific IgE to total IgE ratio was \2.5%. This reflected the more rapid loss of surface cat-specific IgE antibody with anti-IgE therapy in allergic individuals who displayed a more diverse IgE antibody repertoire. We conclude that IgE-specific activity is an age-, IgE heterogeneity-and total serum IgE-dependent variable that influences the magnitude of effector cell mediator release, and by inference, ultimate allergic symptom induction.

Allergen-specific IgE: comparison between skin prick test and serum assay in real life

Allergologie select, 2019

Background: The most common sensitizing allergens in in the area of Liguria region (Northwestern Italy) are pollens, mainly Parietaria and cypress, house dust mites, i.e. Dermatophagoides, and pets. IgE assessment is a crucial step in allergy diagnosis. It may be performed by skin prick test (SPT) or serum IgE (sIgE) assay. Therefore, this study compared these two methods in a real-life setting. Methods: This retrospective study included 793 subjects, who were referred to the Allergy Department for respiratory allergy during 2014. Inclusion criteria were i) documented diagnosis of allergic rhinitis (AR), and/or allergic asthma, and/or allergic conjunctivitis. SPT and sIgE assay were performed for 5 allergens, such as Dermatophagoides pteronyssinus (D1), cat (E1), Parietaria officinalis (W19), cypress (T23), and dog (E5), as they are the most common in our geographic area. Results: Using a positive SPT result as the target condition, remarkably high and statistically significant values of AUC, ranging from 0.84 to 0.94, were found. On the basis of the Youden index the following optimal classification threshold values were also computed: D1 = 0.22, E1 = 0.26, W19 = 0.61, T23 = 0.25, E5 = 0.34. These values allowed to define a set of sensitivity/specifity estimates ranging from 0.75 to 0.93 and from 0.83 to 0.93, respectively. Conclusions: The present study shows that SPT and sIgE are two tests that are rather concordant, but with different sensitivity and specificity distinct for each allergen. In clinical practice, both tests should be used depending on clinical history features and obtained findings.

Accuracy of immunoblotting assay for detection of specific IgE compared with ImmunoCAP in allergic patients

Electronic physician, 2018

Standardized techniques help us to better diagnosis and follow up of allergic diseases. In this study, we determined the sensitivity, accuracy, and specificity of an Immunoblotting test compared to ImmunoCAP as the reference in vitro test for detection of specific IgE in allergic patients. In this cross-sectional study, specific IgE level was determined in patients with allergic symptoms who referred to the Immunology, Asthma and Allergy Research Institute, Tehran, Iran from 2010-2016, by two techniques. Eleven different allergens (six aeroallergens and five food allergens) were determined, and 303 specific IgE tests were performed for the patients by each method. The Immunoblotting test is a multiplex assay on a nitrocellulose membrane coated with 20 selected allergens. ImmunoCAP is considered as the reference method for determination of in vitro specific IgE. Its principle is an automated sandwich immunoassay, and allergens were bound to the solid phase, covalently. Finally, the f...