Detection of Wheat Lipid Transfer Protein (Tri a 14) Sensitization: Comparison between Currently Available Diagnostic Tools

• Published in: International archives of allergy and immunology Vol. 183; no. 1; p. 75
• Main Authors: San Bartolomé, Clara, Muñoz-Cano, Rosa, Rius, Josefina, Casas-Saucedo, Rocío, Balsells, Sara, Egri, Natalia, Ruano-Zaragoza, Maria, de la Cruz, Cinthia, Bartra, Joan, Pascal, Mariona
• Format: Journal Article
• Language: English
• Published: Switzerland 2022
• Subjects: Adolescent; Adult; Aged; Antigens, Plant - immunology; Carrier Proteins - immunology; Clinical Decision-Making; Decision Trees; Disease Management; Female; Humans; Immunization; Immunoassay; Immunoglobulin E - blood; Immunoglobulin E - immunology; Intracellular Signaling Peptides and Proteins - immunology; Male; Middle Aged; Wheat Hypersensitivity - diagnosis; Wheat Hypersensitivity - epidemiology; Wheat Hypersensitivity - immunology; Young Adult; In vitro diagnostic tools; ω5-Gliadin; Specific IgE; Tri a 14 sensitization; Wheat allergy; Cofactor
• ISSN: 1423-0097
• DOI: 10.1159/000517963

Wheat lipid transfer protein (LTP; Tri a 14) and ω5-gliadin have been described as major allergens in wheat allergy (WA) and relevant in wheat-induced anaphylaxis, frequently associated with cofactors. The objective of this study was to compare tools currently available in routine diagnosis to detect Tri a 14 sensitization, its clinical relevance, and cosensitization to ω5-gliadin and other LTPs. One hundred eighteen adults sensitized to rTri a 14 by ImmunoCAP® (cutoff ≥0.1 kUA/L) identified among 210 LTP allergic patients were included. We evaluated (1) wheat skin prick test (SPT), (2) specific IgE (sIgE) to wheat, rTri a 14, rTri a 19, peach, apple, walnut, hazelnut, and peanut LTPs using ImmunoCAP® and microarray ImmunoCAP®ISAC (cutoff ≥0.3I SU), and (3) wheat-related symptoms. Wheat SPT and sIgE were positive in 31% and 85% of subjects, respectively. rTri a 14 by microarray was detected in 25%. Eight percent showed cosensitization to ω5-gliadin. Thirty percent referred symptoms (gastrointestinal [13%], urticaria [11%], and anaphylaxis [8%]). Cofactors (45%) were significantly associated with systemic reactions. WA due to Tri a 14 is frequently related with systemic reactions and because are frequently related to cofactors, the culprit may not be suspected. Together with the poor performance to identify Tri a 14 sensitization of the current routine diagnostic tools based on the analysis of whole wheat extract, such as wheat SPT or sIgE, there is a high risk that WA may be overlooked. Thus, when WA is suspected, sIgE Tri a 14 assessment is recommended, together with wheat and ω5-gliadin, preferably in the singleplex format, and carefully evaluated considering ≥0.1 kUA/L as a cutoff.