title: Generating allergen-specific human IgEs for immunoassays by employing human ε gene knockin mice.
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a knockin homozygous mouse strain, referred to as HεκKI strain, whose gene segment encoding γ1 constant region has been replaced by that encoding human ε constant region and gene segment encoding κ constant region replaced by that encoding human κ constant region.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.
authors.affiliation: Genomics Research Center, Academia Sinica, Taipei, Taiwan.
authors.forename: C S
authors.initials: CS
authors.lastname: Lu
authors.forename: A F
authors.initials: AF
authors.lastname: Hung
authors.forename: C J
authors.initials: CJ
authors.lastname: Lin
authors.forename: J B
authors.initials: JB
authors.lastname: Chen
authors.forename: C
authors.initials: C
authors.lastname: Chen
authors.forename: Y Y
authors.initials: YY
authors.lastname: Shiung
authors.forename: C Y
authors.initials: CY
authors.lastname: Tsai
authors.forename: T W
authors.initials: TW
authors.lastname: Chang
mesh_terms: D000485:Allergens / Q000276:immunology*; D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D061067:Antibodies, Monoclonal, Humanized / Q000276:immunology; D000918:Antibody Specificity; D000941:Antigens / Q000276:immunology; D001491:Basophils / Q000276:immunology; D015550:Cell Degranulation / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay; D023061:Gene Order; D018390:Gene Targeting; D056426:Genetic Loci; D006801:Humans; D006825:Hybridomas; D006967:Hypersensitivity / Q000175:diagnosis / Q000235:genetics / Q000276:immunology; D007114:Immunization; D007118:Immunoassay; D007073:Immunoglobulin E / Q000097:blood / Q000276:immunology*; D007143:Immunoglobulin Heavy Chains / Q000235:genetics; D007147:Immunoglobulin Light Chains / Q000235:genetics; D007139:Immunoglobulin epsilon-Chains / Q000235:genetics*; D007136:Immunoglobulins / Q000097:blood / Q000276:immunology; D051379:Mice; D008822:Mice, Transgenic
chemical_list: D000485:Allergens; D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D000941:Antigens; D007143:Immunoglobulin Heavy Chains; D007147:Immunoglobulin Light Chains; D007139:Immunoglobulin epsilon-Chains; D007136:Immunoglobulins; D007073:Immunoglobulin E
keywords: Chimeric human IgE; IgE hybridoma; allergen-specific IgE antibodies; knockin mice