Correlation of allergen specific immunoglobulin to house dust mites and commensal microbes in atopic dogs and identification of major allergen in dermatophagoides farinae

Abstract

To confirm a causative allergen in atopic dogs could test through intradermal skin testing (IDT) or allergen-specific IgE serology testing (ASIS). ASIS is more practical, convenient and safer. However, the results of ASIS could be affected by source and type of allergen. Crude allergen extracts were still used in commercial testing and protein antigens of skin microbes were not included in the panel of testing. In this study, our group developed serology test for confirming house dust mite allergy called Dermatophagoides farinae and D. pteronyssinus, and measuring specific immunoglobulin to skin microbes on dogs like Malssezia pachydermatis yeast and Staphylococcus pseudintermedius bacteria. The results was found that high IgE levels to house dust mites could be used to differentiate atopic dog with allergy to house dust mites and atopic dogs without allergy to house dust mites. Moreover, IgG1 levels could also use to differentiate house dust mite allergy and non-house dust mite allergy by using lower sample volumes than IgE about 100 times. In the other hand, total IgG and IgG2 levels could not be used to differentiate house dust mite allergy and non-house dust mite allergy in atopic dogs. Both of IgE and IgG1 levels showed the same degrees of agreement to IDT. By investigation through two-dimensional IgE blotting, ten proteins of house dust mites that related to house dust mite allergy in atopic dogs were found, Der f 28 protein is interesting and should be selected to apply for a component-resolved diagnostics. Alpha-enolase, serine protease, and arginine kinase are the critical protein to be a cause of cross reaction. The results of specific immune response to skin microbes were found that atopic dogs had higher specific IgE levels to both skin microbes than healthy dogs. This indicated that skin microbes could act as allergen in atopic dogs. Other specific IgG1 and IgG2 to these skin microbes also high. However, none of any types specific immunoglobulin to skin microbes related to skin severity scores in atopic dogs determining through the Canine Atopic Dermatitis Lesion Index. We concluded that levels of specific immunoglobulin to skin microbes did not relate to skin severity.