2026-03-16 東京大学
図1 尿を用いた食物アレルギー検査法を開発
＜関連情報＞
- https://www.a.u-tokyo.ac.jp/topics/topics_20260316-1.html
- https://onlinelibrary.wiley.com/doi/10.1111/cea.70281
食物アレルギー患者における尿中テトラノール-PGDM検出のための酵素免疫測定法の開発 Development of an Enzyme Immunoassay for Detecting Urinary Tetranor-PGDM in Patients With Food Allergy
Takeru Ishii, Nanae Nagata, Sakura Masuko, Rikako Inoue, Masaki Fujishiro, Tatsuro Nakamura, Kosuke Aritake, Shinya Ogawa, Hisako Ogasawara, Mami Shimada, Yusuke Inuzuka …
Clinical & Experimental Allergy Published: 15 March 2026
DOI:https://doi.org/10.1111/cea.70281
Summary Box
- An enzyme immunoassay (EIA) capable of measuring urinary tetranor-PGDM concentrations was developed.
- The EIA distinguished patients with food allergy from healthy individuals based on urinary tetranor-PGDM concentrations.
To the Editor,
The prevalence of food allergies has been increasing, particularly among children. During food allergic reactions, mast cells release prostaglandin D2 (PGD2), whose urinary metabolite, 9α-hydroxy-11,15-dioxo-13,14-dihydro-2,3,4,5-tetranor-prostan-1,20-dioic acid (tetranor-PGDM) [1], serves as an objective and specific indicator of allergic symptoms during oral food challenges (OFCs) [2-4] and desensitisation in oral immunotherapy [5]. Tetranor-PGDM is excreted in urine, which can be collected non-invasively. To enable versatile measurement of tetranor-PGDM, we developed a monoclonal antibody–based enzyme immunoassay (EIA) [6]. This study aimed to evaluate the utility of this EIA for measuring urinary tetranor-PGDM concentrations and to assess whether these values could distinguish patients with food allergy from healthy individuals.
The antibody used in the assay exhibits higher affinity for 8-((1R,2S)-2-(2-carboxyethyl)-5-oxocyclopent-3-en-1-yl)-6-oxooctanoic acid (tetranor-PGJM), with markedly lower cross-reactivity for other PGD2 metabolites than for tetranor-PGDM. Additional results are shown in online repository material (https://zenodo.org/records/18615641). Tetranor-PGDM is converted into tetranor-PGJM through dehydration. The calibration curve was constructed using tetranor-PGJM concentrations ranging from 0.02 to 5 ng/mL, providing sufficient sensitivity for detecting urinary tetranor-PGJM levels. Interday (five replicates) and intraday (5 days) variations were assessed at concentrations of 0.32, 0.8 and 2 ng/mL, corresponding to the steepest part of the calibration curve. The coefficient of variations (CVs) for interday and intraday experiments ranged from 2.2% to 3.2% and 1.9% to 4.5%, respectively. Recovery rates, evaluated using tetranor-PGJM–spiked phosphate-buffered saline, ranged from 95.7% to 105.4%, confirming the assay’s reliability.
