Anticorpos anti-Demodex canis e Dermatophagoides pteronyssinus em soro de cães com demodicose

Abstract

Canine demodicosis is one of the more common skin diseases encountered in veterinarypractice. Typical lesions are erythematous and alopecic patches on the head and / or forelegs. In order to verify the specific IgG and IgE antibody production against homologous, Demodex canis soluble antigen (SDAg), and heterologous, Dermatophagoides pteronyssinus (SDpt) and Myocoptes musculinus (SMAg) soluble antigens, this study was done. Skin scrapes, blood and serum samples, were collected to analyze the presence of the acarian in the skin, eosinophils and antibody production by ELISA, respectively. The samples were collected from 27 dogs, 3 from healthy dogs that were more than 12 months old, 20 from dogs with skin lesions and 4 from healthy young dogs (less than 12 months old). The homologous antigen was not able to discriminate between positive and negative control serum samples. When heterologous antigens were used to detect IgG antibodies, both of them were not able to discriminate symptomatic and non symptomatic dogs. In addition, it was observed that young dogs (those with less than 12 months old) symptomatic and non symptomatic dogs were reactive to heterologous ntigen. However, when heterologous antigens were used to detect IgE antibodies, it was observed that symptomatic dogs presented IgE specific antibodies when they were more than 12 months old. The non symptomatic dogs did not presented specific antibody against heterologous antigens. Additionally, soluble antigens from D. canis, D. pteronyssinus and M. musculinus presented some proteins with similar molecular weigth. These data suggest that D. canis and related parasites D. pteronyssinus and M. musculinus shared some antigens that induce production of cross reactive antibodies.