Measurement of canine IgE using the alpha chain of the human high affinity IgE receptor

Measurement for Canine IgE Using Canine Recombinant High Affinity IgE Receptor α Chain (FcεRIα)

“…Similar to the evaluation of human FcεRIα [27], we demonstrated IgE isotype specificity for the canine FcεRIα using ELISA for solid phase bound purified canine IgE and purified canine IgG. Our purified canine FcεRIα bound to canine IgE in an antigen dose dependent fashion that showed reactivity at concentrations as little as 3 ng, but reactivity of the purified canine FcεRIα to canine IgG was completely lacking even at a concentration of 100 ng.…”

“…Multiple in vitro assays for detection of allergen-specific IgE are available in the veterinary arena [9,12,16,17,20,23,26], yet there is a paucity of useful data describing the assays and comparing the available tests. The best characterized assays for detection of allergen-specific IgE in dogs are a monoclonal antibody cocktail-based ELISA for dog specific IgE [17] and a human high affinity IgE receptor based assay for dog IgE [6,27]. When directly compared, the concordance of results for these 2 assays was demonstrated to be approximately 92% which is similar to the intra-ELISA/inter-laboratory concordance of results [17].…”

“…The utility of this molecule in detecting antigen-specific IgE in human sera as well as a variety of other animals has been well documented. In fact, one of the characterized commercial ELISA for allergen specific IgE in dogs [27] incorporates a human high affinity FcεRIα. However, Hakimi et al reported that human FcεRIα exhibited lower affinity for rat IgE when compared to the affinity for human IgE [10] and it is likely that lowered cross species affinity exists for human FcεRIα in other animals as well.…”

“…Although the performance characteristics of this detection reagent in an all encompassing allergen-specific IgE ELISA remains to be determined, it is logical to assume that its performance in detecting allergen-specific IgE in dog sera will parallel and exceed the performance characteristic of the human FcεRIα currently being used [27]. In essence, the FcεRIα behaves as a single epitope detecting tracer molecule.…”

Monitoring of basophil sensitization to antigens of the cat flea (Ctenocephalides felis felis): a new tool for the diagnosis of feline flea bite hypersensitivity?

“…Streptavidin alkaline phosphatase was used as the enzyme containing secondary tracer and p-nitrophenyl phosphate as substrate. Plates were coated with either a preparation of Greer flea whole-body extract (4 μg/ml) or a mixture of native flea saliva (1.25 μg/ml) and a recombinant protein of the flea salivary antigen Cte f 1 (0.625 μg/ml) (McCall et al 1997;Stedman et al 2001). The test was considered positive when the titres were ≥150 EA units (cutoff determined by Heska Corp.).…”