DeMartini J C, Halsey W, Boshoff C, York D, Howell M D
Department of Pathology, Colorado State University, Fort Collins 80523, USA.
Vet Immunol Immunopathol. 1999 Oct 1;71(1):29-40. doi: 10.1016/s0165-2427(99)00083-5.
A maedi-visna virus CA-TM fusion protein ELISA (MVV ELISA) was evaluated for the detection of antibody in sheep infected with North American ovine lentivirus (OvLV). The results of the MVV ELISA were compared with other assays for OvLV antibody and with viral infection in an intensively studied group of 38 sheep with a high prevalence of OvLV infection and disease. The sensitivity, specificity, and concordance of assays for OvLV antibody (MVV ELISA, indirect ELISA, Western blot, and AGID), virus (virus isolation, PCR, antigen ELISA), and OvLV-induced disease in each animal were compared with OvLV infection status as defined by a positive result in two or more of the assays. Five sheep met the criteria for absence of OvLV infection. The sensitivity of the MVV ELISA in detecting OvLV infected sheep was 64%, whereas the sensitivity of the other three tests for antibody ranged from 85 to 94%. All the antibody assays were 100% specific in this group of animals. Of the assays for virus, the PCR test had the highest sensitivity and the best concordance with OvLV infection, but it also had the lowest specificity of any of the virus or antibody assays. Among the antibody tests, the concordance of the MVV ELISA compared most favorably with the AGID test for detecting OvLV-infected sheep. Analysis of serum samples from 28 lambs experimentally-infected with one of three North American strains of OvLV suggested that there were no significant strain differences detectable by antibody assay. Twenty virus-inoculated lambs were positive by both the MVV ELISA and the AGID test, five lambs were MVV ELISA negative and AGID test positive, and three lambs were MVV ELISA positive and AGID test negative. No pre-inoculation samples were positive by either assay. In a longitudinal study involving seven lambs, antibodies to OvLV were detected by AGID 3-5 weeks post-inoculation, but were not detected by MVV ELISA until 5-10 weeks post-inoculation. Among 128 naturally and experimentally-infected sheep that were seropositive in the AGID test, the overall sensitivity of the MVV ELISA was higher in the naturally infected sheep (84%) than in the experimentally infected sheep (69%). The data indicated that the MVV ELISA represents a less sensitive, but specific alternative for the detection of OvLV antibodies.
评估了梅迪 - 维斯纳病毒CA - TM融合蛋白酶联免疫吸附测定法（MVV ELISA）用于检测感染北美绵羊慢病毒（OvLV）的绵羊体内抗体的效果。将MVV ELISA的结果与其他检测OvLV抗体的方法以及在一组经过深入研究的38只绵羊中的病毒感染情况进行了比较，这些绵羊中OvLV感染和疾病的患病率很高。将每只动物的OvLV抗体检测方法（MVV ELISA、间接ELISA、蛋白质印迹法和琼脂凝胶免疫扩散试验）、病毒检测方法（病毒分离、聚合酶链反应、抗原ELISA）以及OvLV引发疾病的敏感性、特异性和一致性与通过两种或更多种检测方法呈阳性结果所定义的OvLV感染状态进行了比较。五只绵羊符合无OvLV感染的标准。MVV ELISA检测OvLV感染绵羊的敏感性为64%，而其他三种抗体检测方法的敏感性在85%至94%之间。在这组动物中，所有抗体检测方法的特异性均为100%。在病毒检测方法中，聚合酶链反应检测的敏感性最高，与OvLV感染的一致性最好，但它在所有病毒或抗体检测方法中的特异性也是最低的。在抗体检测方法中，MVV ELISA在检测OvLV感染绵羊方面与琼脂凝胶免疫扩散试验的一致性最为良好。对28只经实验感染三种北美OvLV毒株之一的羔羊的血清样本分析表明，通过抗体检测未发现明显的毒株差异。20只接种病毒的羔羊通过MVV ELISA和琼脂凝胶免疫扩散试验均呈阳性，5只羔羊MVV ELISA阴性但琼脂凝胶免疫扩散试验阳性，3只羔羊MVV ELISA阳性但琼脂凝胶免疫扩散试验阴性。接种前的样本通过两种检测方法均未呈阳性。在一项涉及7只羔羊的纵向研究中，接种后3 - 5周通过琼脂凝胶免疫扩散试验检测到OvLV抗体，但直到接种后5 - 10周才通过MVV ELISA检测到。在128只自然感染和实验感染且琼脂凝胶免疫扩散试验呈血清阳性的绵羊中，MVV ELISA在自然感染绵羊中的总体敏感性（84%）高于实验感染绵羊（69%）。数据表明，MVV ELISA是检测OvLV抗体的一种敏感性较低但具有特异性的替代方法。
