| 摘要 |
Canine monocytic ehrlichiosis, caused by <i>Ehrlichia canis</i> is a potentially fatal disease of dogs that requires rapid and accurate diagnosis in order to initiate appropriate therapy leading to a favorable prognosis. In the invention described herein, a new immunoreactive <i>E. canis</i> surface protein gene of 1170-bp was cloned, which encodes a protein with a predicted molecular mass of 42.6 kilodaltons (P43). The P43 gene was not found in <i>E. chaffeensis</i> DNA by Southern blot, and antisera against recombinant P43 (rP43) did not react with <i>E. chaffeensis</i> by IFA. The P43 was located on the surface of <i>E. canis</i> by immunoelectron microscopy. Forty-two dogs exhibiting signs and/or hematologic abnormalities associated with canine ehrlichiosis were tested by IFA and by Western immunoblot. Among the 22 samples that were IFA positive for <i>E. canis</i>, 100 % reacted with the rP43, 96 % with the rP28, and 96 % with the rP140. The specificity of the recombinant proteins compared to IFA was 96 % for rp28, 88 % for P43 and 63 % for P140. Results of this study demonstrate that the rP43 and rP28 are sensitive and reliable serodiagnostic antigens for the diagnosis of Ehrlichia canis infections. |
