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Updated: Jun 14, 2026
Measuring Local Anaphylaxis in Mice
Published on: October 14, 2014
A convenient and sensitive allergy test: IgE crosslinking-induced luciferase expression in cultured mast cells
Ryosuke Nakamura1, Y Uchida, M Higuchi
1Division of Novel Foods and Immunochemistry, National Institute of Health Science, Setagaya-ku, Tokyo, Japan. ryosnak@nihs.go.jp
Background:
For the detection of allergen-specific IgE in sera, solid-phase IgE-binding assays like the CAP test are commonly used. Although such immunochemical methods are very sensitive, they frequently produce false positives. Degranulation of the human IgE receptor (FcεRI)-transfected rat mast cell (RBL) lines seems to be a possible indicator for human IgE, but spontaneous mediator release from these cells in the presence of human sera is not negligible.
Methods:
The nuclear factor of activated T-cells (NFAT)-responsive luciferase reporter gene was stably transfected into human FcεRI-expressing RBL-SX38 cells. One established clone (RS-ATL8) was sensitized with 1 : 100 dilution of sera from patients with egg white allergy and then stimulated with purified or a crude extract of egg white allergen.
Results:
Sensitization with 15 pg/ml IgE was sufficient to detect IgE crosslinking-induced luciferase expression (EXiLE) by anti-IgE stimulation. Allergen-specific EXiLE was elicited by as little as 1 fg/ml of egg white protein without cytotoxicity. There was a good correlation between results with EXiLE and oral food challenge tests on patients with egg allergy (P = 0.001687, Fisher's exact test). The measured values of EXiLE and the CAP test also correlated well (R = 0.9127, Spearman's test).
Conclusion:
The EXiLE test using RS-ATL8 cells is a promising in vitro IgE test to evaluate the biological activity of the binding between IgE and allergens.
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