Defining specific allergens for improved component-resolved diagnosis of shrimp allergy in adults. (August 2019)

• Record Type: Journal Article
• Authors: Johnston, Elecia B.; Kamath, Sandip D.; Iyer, Swati P.; Pratap, Kunal; Karnaneedi, Shaymaviswanathan; Taki, Aya C.; Nugraha, Roni; Schaeffer, Patrick M.; Rolland, Jennifer M.; O'Hehir, Robyn E.; Lopata, Andreas L.
• Is Part Of: Molecular immunology. Volume 112(2019:Aug.)
• Page Start: 330
• Page End: 337
• Publication Date: 2019-08
• Subjects: sIgE specific IgE -- TM tropomyosin -- AK arginine kinase -- SCP sarcoplasmic calcium-binding protein -- HC hemocyanin; Component-resolved diagnosis -- IgE antibody -- Immuno-PCR -- Shrimp allergens -- Tropomyosin; Immunochemistry -- Periodicals; Molecular biology -- Periodicals; Immunochemistry -- Periodicals; Allergy and Immunology -- Periodicals; Molecular Biology -- Periodicals; Immunochimie -- Périodiques; Biologie moléculaire -- Périodiques; Immunochemistry; Molecular biology; Periodicals; Electronic journals; 571.96
• DOI: 10.1016/j.molimm.2019.05.006
• Languages: English
• ISSNs: 0161-5890

Abstract

Highlights: 62% of clinically confirmed shrimp-allergic adults were positive by commercial in vitro testing. IgE binding to the well-known allergen tropomyosin occurred in only 43% of shrimp allergic adults. 52% of patients demonstrated IgE binding to additional allergens. Considerable IgE binding was observed to arginine kinase, hemocyanin and sarcoplasmic calcium-binding protein. Abstract: Shrimp is one of the predominant causes of food allergy among adults, often presenting with severe reactions. Current in vitro diagnostics are based on quantification of patient specific-IgE (sIgE) to shrimp extract. Tropomyosin is the known major shrimp allergen, but IgE sensitisation to other allergens is poorly characterised. In this study, the binding of IgE to various shrimp allergens, additional to tropomyosin, was investigated using sera from 21 subjects who had clinical reactions to one or more shellfish species. Total shrimp-sIgE was quantified using ImmunoCAP, while allergen-sIgEs were quantified using immunoblotting and mass spectrometry, and immuno-PCR to recombinant shrimp tropomyosin. Sixty-two percent of subjects (13/21) were positive to shrimp by ImmunoCAP. IgE from 43% of subjects (9/21) bound tropomyosin, while an additional 29% of subjects (6/21) demonstrated IgE-binding solely to other shrimp allergens, including sarcoplasmic calcium-binding protein, arginine kinase and hemocyanin. Furthermore, IgE sensitisation to other shrimp allergens was demonstrated in 50% of subjects (4/8) who were ImmunoCAP negative. The lack of standardised shrimp allergens and inadequacy of current extracts for shrimp allergy diagnosis is highlighted by this study. Comprehensive knowledge of less studied allergens and their inclusion in component-resolved diagnostics will improve diagnostic accuracy, benefitting the wider population suffering from shellfish allergy.