Generating allergen‐specific human IgEs for immunoassays by employing human ε gene knockin mice. Issue 4 (11th February 2015)

• Record Type: Journal Article
• Authors: Lu, C.‐S.; Hung, A. F.; Lin, C.‐J.; Chen, J.‐B.; Chen, C.; Shiung, Y.‐Y.; Tsai, C.‐Y.; Chang, T. W.
• Is Part Of: Allergy. Volume 70:Issue 4(2015:Apr.)
• Page Start: 384
• Page End: 390
• Publication Date: 2015-02-11
• Subjects: allergen‐specific IgE antibodies -- Chimeric human IgE -- IgE hybridoma -- knockin mice; Allergy -- Periodicals; 616.97
• DOI: 10.1111/all.12572
• Languages: English
• ISSNs: 0105-4538

Abstract

Abstract: Background: Antigen‐specific human IgEs are important reagents in immunoassays to quantify antigen‐specific IgEs in allergic patients, but they are not easy to prepare. Methods: We constructed a knockin homozygous mouse strain, referred to as HεκKI strain, whose gene segment encoding γ1 constant region has been replaced by that encoding human ε constant region and gene segment encoding κ constant region replaced by that encoding human κ constant region. The mice were tested for their ability to produce antigen‐specific chimeric human IgE (with mouse variable regions) upon the immunization with ovalbumin and papain. Subsequently, the spleen cells from the immunized mice were used as the source of B cells for the preparation of hybridomas, which secreted monoclonal human IgE antibodies specific for the antigens. Results: The HεκKI mice expressed human IgE (ε, κ) in serum at levels 10‐ to 30‐fold higher than those of mouse IgE. Upon immunization with an antigen, the mice yielded splenic B cells for preparing hybridomas that secrete chimeric human IgE specific for the antigen. Purified IgEs from those hybridomas could activate a basophilic cell line to undergo degranulation upon the stimulation with their respective antigens. Conclusions: We have developed a human ε gene and κ gene knockin mouse strain, which is useful for producing various antigen‐specific chimeric human IgEs for potential use as standards in immunoassays.