scholarly journals CytoBas: Precision component-resolved diagnostics for allergy using flow cytometric staining of basophils with recombinant allergen tetramers

Author(s):  
Craig McKenzie ◽  
Nirupama Varese ◽  
Pei Aui ◽  
Bruce Wines ◽  
P Hogarth ◽  
...  

Background: Diagnostic tests for allergy rely on detecting allergen-specific IgE. Component-resolved diagnostics incorporate multiple defined allergen components to improve the quality of diagnosis and patient care. Objective: To develop a new approach for determining sensitization to specific allergen components that utilizes fluorescent protein tetramers for direct staining of IgE on blood basophils by flow cytometry. Methods: Recombinant forms of Lol_p_1 and Lol_p_5 proteins from ryegrass pollen (RGP) and Api_m_1 from honeybee venom (BV) were produced, biotinylated and tetramerized with streptavidin-fluorophore conjugates. Blood samples from 50 RGP-allergic, 41 BV-allergic and 26 controls were incubated with fluorescent protein tetramers for flow cytometric evaluation of basophil allergen binding and activation. Results: Allergen tetramers bound to and activated basophils from relevant allergic patients but not controls. Direct fluorescence staining of Api_m_1 and Lol_p_1 tetramers had greater positive predictive values than basophil activation for BV and RGP allergy, respectively, as defined with receiver operator characteristics (ROC) curves. Staining intensities of allergen tetramers correlated with allergen-specific IgE levels in serum. Inclusion of multiple allergens coupled with distinct fluorochromes in a single tube assay enabled rapid detection of sensitization to both Lol_p_1 and Lol_p_5 in RGP-allergic patients and discriminated between controls, BV-allergic and RGP-allergic patients. Conclusion: Our novel flow cytometric assay, termed CytoBas, enables rapid and reliable detection of clinically relevant allergic sensitization. The intensity of fluorescent allergen tetramer staining of basophils has a high positive predictive value for disease and the assay can be multiplexed for a component-resolved and differential diagnostic test for allergy.

2020 ◽  
pp. 028418512098177
Author(s):  
Yu Lin ◽  
Nannan Kang ◽  
Jianghe Kang ◽  
Shaomao Lv ◽  
Jinan Wang

Background Color-coded multiphase computed tomography angiography (mCTA) can provide time-variant blood flow information of collateral circulation for acute ischemic stroke (AIS). Purpose To compare the predictive values of color-coded mCTA, conventional mCTA, and CT perfusion (CTP) for the clinical outcomes of patients with AIS. Material and Methods Consecutive patients with anterior circulation AIS were retrospectively reviewed at our center. Baseline collateral scores of color-coded mCTA and conventional mCTA were assessed by a 6-point scale. The reliabilities between junior and senior observers were assessed by weighted Kappa coefficients. Receiver operating characteristic (ROC) curves and multivariate logistic regression model were applied to evaluate the predictive capabilities of color-coded mCTA and conventional mCTA scores, and CTP parameters (hypoperfusion and infarct core volume) for a favorable outcome of AIS. Results A total of 138 patients (including 70 cases of good outcomes) were included in our study. Patients with favorable prognoses were correlated with better collateral circulations on both color-coded and conventional mCTA, and smaller hypoperfusion and infarct core volume (all P < 0.05) on CTP. ROC curves revealed no significant difference between the predictive capability of color-coded and conventional mCTA ( P = 0.427). The predictive value of CTP parameters tended to be inferior to that of color-coded mCTA score (all P < 0.001). Both junior and senior observers had consistently excellent performances (κ = 0.89) when analyzing color-coded mCTA maps. Conclusion Color-coded mCTA provides prognostic information of patients with AIS equivalent to or better than that of conventional mCTA and CTP. Junior radiologists can reach high diagnostic accuracy when interpreting color-coded mCTA images.


2018 ◽  
Vol 93 (5) ◽  
pp. 556-562 ◽  
Author(s):  
Benjamin Kleeman ◽  
Andre Olsson ◽  
Tess Newkold ◽  
Matt Kofron ◽  
Monica DeLay ◽  
...  

2021 ◽  
Vol 49 (2) ◽  
pp. 6-14
Author(s):  
Huang Lunhui ◽  
Shao Yanhong ◽  
Li Shaoshen ◽  
Bao Huijing ◽  
Liu Yunde ◽  
...  

Introduction and objectives: It was urgent to explain the role of egg yolk allergen sensitization to the egg allergic population and we would evaluate the diagnostic value of allergen components in whole eggs, including egg white and egg yolk.Materials and methods: Firstly, we collected 99 positive and 21 negative sera against egg allergy. Then we used modified enzyme linked immunosorbent assay (ELISA) to survey specific IgE (sIgE) to all-proven and single component in eggs, Ovomucoid (Gal d 1), Ovalbumin (Gal d 2), Ovotransferrin (Gal d 3), Lysozyme C (Gal d 4), Serum Albumin (Gal d 5), and YGP42(Gal d 6) in allergic and non-allergic populations. Last but not least, we studied the sIgE reactivities to egg allergen components by receiver operating characteristic (ROC) analysis.Results: Among egg-allergic individuals, nearly 10% were sensitized to five of six egg allergen components, and the cross-reaction frequency between two egg yolk allergens with Gal d 1 was about 30% in the groups diagnosed with egg allergy or non-allergy. The best component-combination diagnosis in egg allergy of Gal d 1+ Gal d 6 demonstrated the largest area under curve (AUC) of 0.994.Conclusions: Our results suggested that there were individual differences in allergenicity of different egg allergen components, especially in the samples negative to egg allergy diagnosed but sensitive to egg yolk components. It was indicated that component resolved diagnosis of egg yolk improved the value for egg allergy management indispensably.


2021 ◽  
pp. 22-31
Author(s):  
V.G. Vakulchyk ◽  
◽  
A.V. Kapytski ◽  

Acute nonspecific abdominal pain in children is the most common problem requiring differential diagnosis with acute appendicitis. Scales for integrated assessment of individual symptoms and their combinations have been proposed and are constantly being developed that allow predicting the likelihood of acute appendicitis. Purpose to assess diagnostic value of Pediatric Appendicitis Score (PAS) in groups of children in different ages. Materials and methods. 374 children aged 4 to 15 years with acute abdominal pain were evaluated in prospective randomized blinded study. Statistical analysis: ROC – curves, specificity and sensitivity, positive and negative predictive values; Kullback criteria; logistic regression analysis; discriminant analysis. Results. Detection frequency and diagnostic significance of the PAS scale predictors as well as obtained results by using the Pediatric Appendicitis Score depend on children age significantly. In terms of diagnosis of acute appendicitis, the PAS scale shows the best results in older children. Conclusions. Results of Pediatric Appendicitis Score depend on children ages due to different diagnostic value of predictors used in the PAS scale. Pediatric surgeons should keep in your mind these data. Modification of the scale is required taking into account the patient’s age. Further analysis of the issue of PAS using is needed. The research was carried out in accordance with the principles of the Helsinki Declaration. The study protocol was approved by the Local Ethics Committee of these Institutes. The informed consent of the patient was obtained for conducting the studies. The authors declare no conflicts of interests. Key words: acute appendicitis, children, diagnosis, PAS scale.


2017 ◽  
Vol 24 (3) ◽  
pp. 145-152
Author(s):  
Rūta Dubakienė ◽  
Vilija Rubinaitė ◽  
Malvina Petronytė ◽  
Indrė Dalgėdienė ◽  
Odilija Rudzevičienė ◽  
...  

Background. Allergic diseases are the most prevalent chronic diseases in the developed countries. It is believed that early allergic sensitization and respiratory viral infections play an important role in the development of allergic diseases and asthma. Methods. The current study investigated the correlation between asthma, allergy, and various markers – allergen-specific IgE, IgG4 and IgA, ECP, IgM, and IgG antibodies against respiratory viruses hRSV and hPIV1-4 – in blood serum samples from 80 children (mean age 5.2 years) recruited from the Lithuanian birth cohort. Children were divided into three groups according to their diagnosis: asthma (n = 25), allergy without asthma (n = 14), and control group (n = 41). Results. Based on retrospective data, airway infections and bronchitis by the age of two years were associated with asthma in later childhood. The presence of IgM and IgG antibodies against hRSV and hPIV1–4 at the age of five years were not associated with asthma and allergy: a high rate of persistent or past respiratory viral infections was revealed in all three groups. Among allergic children, increased levels of allergen-specific IgE and d1-specific IgG4 were determined. Conclusion. The current study provides new insights into the relationships between allergic sensitization and respiratory virus infections in children.


2018 ◽  
Author(s):  
Mitchell H. Grayson ◽  
Peter Mustillo

The incidence of allergic diseases, like asthma, allergic rhinitis, and food allergy, is increasing in Westernized countries. This chapter discusses the importance of taking a careful and focused history and physical examination, as well as the laboratory studies that can be used to demonstrate the presence of allergic sensitization. Treatment for allergic disease is discussed, with an emphasis on new biologic therapies that have been developed. Finally, the chapter explores relatively new studies on the potential for interventions to prevent food allergy.  Allergy is defined as an untoward physiologic event mediated by immune mechanisms, usually involving the interaction between an allergen and the allergic antibody, immunoglobulin E (IgE). Allergic reactions typically occur due to exposure to either airborne allergens, foods, drugs, chemicals, or Hymenoptera (such as wasps, bees and fire ants). Allergies manifest in numerous ways, including allergic asthma, allergic rhinoconjunctivitis, urticaria, eczema, and in its most severe form, anaphylaxis. This review contains 4 videos, 5 figures, 4 tables and 42 references Key Words: Delayed allergic reaction (Alpha-gal), Allergy diagnosis, Measurement of specific IgE, Allergy and asthma therapies, Anticytokine therapy (dupilumab, mepolizumab, reslizumab), AntiIgE therapy (omalizumab), Allergy skin testing, Basophil histamine release assay


2020 ◽  
Author(s):  
Le Qian ◽  
Qinwen Du ◽  
Meijiao Jiang ◽  
Fei Yuan ◽  
Hui Chen ◽  
...  

Abstract Background This study aimed to compare different ultrasound-based International Ovarian Tumor Analysis (IOTA) prediction models, namely, the Simple Rules (SRs) the Assessment of Different NEoplasias in the adneXa (ADNEX) models, and the Risk of Malignancy Index (RMI), for the pre-operative diagnosis of adnexal mass. Methods This single-centre, retrospective study of diagnostic accuracy involved 486 patients. All ultrasound examinations were analyzed and the prediction models were applied. Pathology was the clinical reference standard. The diagnostic performances of prediction models were measured by evaluating receiver-operating characteristic (ROC) curves, sensitivities, specificities, positive and negative predictive values, positive and negative likelihood ratios, and diagnostic odds ratios. Results To discriminate benign and malignant tumours, areas under the ROC curves (AUCs) for ADNEX models were 0.94 (95% CI: 0.92–0.96) with CA125 and 0.94 (95% CI: 0.91–0.96) without CA125, which were significantly higher than the AUCs for RMI I-III: 0.87 (95% CI: 0.83–0.90), 0.83 (95% CI: 0.80–0.86), and 0.82 (95% CI: 0.78–0.86), (all P < 0.0001). At a cut-off of 10%, the ADNEX model with CA125 had the highest sensitivity (0.93; 95% CI: 0.87–0.97) compared with the other models. The SRs model achieved a sensitivity of 0.93 (95% CI: 0.86–0.97) and a specificity of 0.86 (95% CI: 0.82–0.89) when inconclusive diagnoses (11.7%) were classified as malignant. Conclusion ADNEX and SRs models were excellent at characterising adnexal masses which were superior to the RMI in Chinese patients.


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