Serum IgE cross-reactivity between fish and chicken meats in dogs.

Background: In humans, a cross-reactive clinical allergy has been reported between three chicken and fish meat proteins: beta-enolase, aldolase A and parvalbumin.

Objective: To evaluate if IgE cross-reactivity between chicken and fish also existed in the dog.

Animals: Sera from dogs with suspected allergic skin disease and with IgE against chicken and fish.

Methods And Materials: Sera were analysed by ELISA and immunoblotting with chicken, white fish (haddock and cod) and salmon extracts. Reciprocal inhibition ELISAs and inhibition immunoblots were then performed. Protein sequencing of bands identified on multiple extracts was determined by mass spectrometry.

Results: Out of 53 archived canine sera tested by ELISA against chicken, white fish or salmon, 15 (28%), 12 (23%) and 26 (49%), respectively, had elevated IgE against one, two or all three of these extracts. Seven of the triple-reactive sera were subjected to reciprocal inhibition ELISAs. A >50% inhibition was found between chicken-fish, chicken-salmon and fish-salmon in seven, four and five of seven dogs, respectively. Immunoblotting identified multiple IgE-binding proteins of identical molecular weights in the three extracts; these were partially to fully cross-reactive by inhibition immunoblotting. Mass spectrometry identified nine cross-reactive proteins as: pyruvate kinase, creatine kinase, alpha-actin, glyceraldehyde-3-phosphate dehydrogenase, beta-enolase, aldolase, malate dehydrogenase, lactate dehydrogenase and triose-phosphate isomerase 1. All of these have been reported previously as fish, shellfish and/or chicken allergens for humans.

Conclusions And Clinical Importance: Whether any of these newly identified IgE cross-reactive chicken-fish allergens is the cause of clinical allergy needs to be determined in dogs reacting to at least two of these common food sources.