Gaunt S D, Corstvet R E, Berry C M, Brennan B
Department of Veterinary Pathology, School of Veterinary Medicine, Louisiana State University, Baton Rouge 70803, USA.
J Clin Microbiol. 1996 Jun;34(6):1429-32. doi: 10.1128/jcm.34.6.1429-1432.1996.
Subcutaneous inoculation of dogs with Ehrlichia canis was investigated as a more appropriate model of canine ehrlichiosis, which is naturally transmitted by arthropod vectors. A dose-dependent response occurred following subcutaneous inoculation of seven groups of dogs with log concentrations of E. canis-infected canine-origin cells. Ehrlichial infection in dogs was defined as concurrence of an increased titer of anti-E. canis immunoglobulin G (IgG) antibody in serum, a decreased platelet concentration, and isolation of E. canis by blood culture. In dogs administered the two lowest doses, no changes were detected. In seven of nine dogs administered three intermediate doses, the only change detected was a transient and mild increase in the anti-E. canis IgG antibody titer in serum. Only two of nine dogs inoculated with the intermediate doses developed an ehrlichial infection. Five of six dogs administered the two highest dose of E. canis developed an ehrlichial infection. These dogs had the highest IgG antibody titers in serum and the earliest isolation of E. canis from blood. In dogs that developed an ehrlichial infection, thrombocytopenia occurred by 28 days after inoculation, while increased IgG antibody titers in serum and blood cultures positive for E. canis occurred as early as 14 days postinoculation. Thrombocytopenia and seroconversion occurred later in the course of infection than previously reported for ehrlichial infections induced by intravenous inoculation. The route of administration and E. canis inoculum size can influence the course of ehrlichial infection and should be regarded as important variables in experimentally induced canine ehrlichiosis.
对犬进行犬埃立克体的皮下接种进行了研究，以建立一种更合适的犬埃立克体病模型，该病自然情况下通过节肢动物媒介传播。用对数浓度的感染犬埃立克体的犬源细胞对七组犬进行皮下接种后出现了剂量依赖性反应。犬的埃立克体感染定义为血清中抗犬埃立克体免疫球蛋白G（IgG）抗体滴度升高、血小板浓度降低以及通过血培养分离出犬埃立克体。给予最低两个剂量的犬未检测到变化。给予三个中间剂量的九只犬中有七只，唯一检测到的变化是血清中抗犬埃立克体IgG抗体滴度短暂轻度升高。接种中间剂量的九只犬中只有两只发生了埃立克体感染。给予犬埃立克体最高两个剂量的六只犬中有五只发生了埃立克体感染。这些犬血清中的IgG抗体滴度最高，且最早从血液中分离出犬埃立克体。发生埃立克体感染的犬，接种后28天出现血小板减少，而血清中IgG抗体滴度升高以及犬埃立克体血培养呈阳性最早在接种后14天出现。血小板减少和血清转化在感染过程中出现的时间比先前报道的静脉接种诱导的埃立克体感染要晚。给药途径和犬埃立克体接种量可影响埃立克体感染的进程，应被视为实验性诱导犬埃立克体病的重要变量。
