Establishment of a quantitative ELISA for the measurement of allergen-specific IgE in dogs using anti-IgE antibody cross-reactive to mouse and dog IgE.
As IgE plays a pivotal role in type I hypersensitivity-mediated allergic diseases, it is valuable to measure absolute quantity of serum antigen-specific IgE for clinical and research purposes. Here we describe a novel ELISA system that enables quantification of antigen-specific IgE in ng/ml in dogs. A newly developed monoclonal antibody (CRE-DM) was shown to recognize canine and mouse IgE equally in a dose dependent manner, but it did not recognize canine IgG. The reactivity of CRE-DM to canine IgE was also confirmed by an inhibition ELISA using canine IgE as an inhibitor and the maximum inhibition rate was 91.3%. In order to know whether canine IgE specific to an allergen could be quantitatively measured with an ELISA using CRE-DM, we established a quantitative ELISA that could measure canine IgE recognizing Cry j 1, one of the major allergens of Japanese cedar pollen. In this ELISA, a standard curve was created by using concentration-predetermined Cry j 1-specific monoclonal mouse IgE. According to the standard curve, the concentration of Cry j 1-specific IgE in dogs that were experimentally sensitized to Japanese cedar pollen could be calculated and determined in ng/ml. The specificity of the Cry j 1-specific IgE ELISA using CRE-DM was also confirmed by inhibition ELISA using canine IgE as an inhibitor and the inhibition rate was 97.0%. Reproducibility of the ELISA in three independent assays was determined using groups of pooled canine sera whose Cry j 1-IgE titers ranged from 155.9 to 888.2 ng/ml. Intra- and inter-assay reproducibility was determined with coefficient of variation ranging between 3.1-5.2% and 2.2-8.0%, respectively. These results demonstrated that the ELISA utilizing CRE-DM was a specific, reliable and robust new laboratory test that could quantify absolute amount of antigen-specific IgE in canine serum. The ELISA will serve as a useful tool in the clinics to evaluate the change of serum IgE titers during anti-allergic treatments as well as during seasonal fluctuation of allergen exposure.
Animal Allergy Clinical Laboratories Inc., SIC-2 #301 5-4-30 Nishihashimoto, Midori-ku, Sagamihara, Kanagawa 229-1131, Japan.
Taro
T
Okayama
Yukiko
Y
Matsuno
Nobutaka
N
Yasuda
Toshihiro
T
Tsukui
Yasuyuki
Y
Suzuta
Masanori
M
Koyanagi
Masahiro
M
Sakaguchi
Yasuyuki
Y
Ishii
Thierry
T
Olivry
Kenichi
K
Masuda
D000485:Allergens / Q000276:immunology*; D000818:Animals; D000888:Antibodies, Anti-Idiotypic / Q000276:immunology*; D000918:Antibody Specificity / Q000276:immunology*; D004285:Dogs; D004797:Enzyme-Linked Immunosorbent Assay / Q000662:veterinary*; D005260:Female; D007073:Immunoglobulin E / Q000276:immunology*; D051379:Mice; D051381:Rats; D017208:Rats, Wistar
D000485:Allergens; D000888:Antibodies, Anti-Idiotypic; C026408:anti-IgE antibodies; D007073:Immunoglobulin E