检测猪乙型脑炎病毒抗体间接ELISA方法的建立与应用

以乙型脑炎病毒(JEV)弱毒疫苗株作为诊断抗原,对ELISA反应条件进行优化,初步建立了检测猪乙型脑炎病毒血清抗体的间接ELISA方法。应用该法检测从江苏、安徽、山东、浙江4省部分地区收集到的1089份血样,对华东地区猪乙型脑炎血清流行病学进行初步调查。结果JEV抗体阳性率为68.2%,其中,种猪JEV抗体阳性率为82.1%,商品猪JEV抗体阳性率为62.6%。从中随机抽取135份血样与国产商品化试剂盒进行比较,间接ELISA方法的特异性和敏感性分别为92%和96.4%,2种方法的符合率为95.6%;与NS1蛋白包被建立的ELISA比较,两者的符合率为97.7%;同时,本法的阳性检出率显著高于临床普遍使用的乳胶凝集试验结果。由此表明,本试验建立的间接ELISA方法具有较高的敏感性和特异性,适于大规模猪乙型脑炎血清流行病学调查。

Development and application of an indirect ELISA method for detection of antibody to porcine Japanese encephalitis virus

The indirect ELISA with one strain living-attenuated vaccine of Japanese encephalitis virus (JEV) as diagnostic antigen was established and optimized to detect antibodies against JEV in porcine sera. In order to investigate the seroepidemiology of porcine Japanese encephalitis in East China, the indirect ELISA was used to test against 1 089 serum samples collected from some areas of Jiangsu, Anhui, Shandong and Zhejiang provinces, and 68.2% of samples were antibody-positive to JEV. Precisely, the positive rates of antibody to JEV in samples of breeding and market pigs were 82.1% and 62.6%, respectively. Based on the data obtained from 135 randomly picked serum samples, the specificity and sensitivity of the indirect ELISA were 92% and 96.4%, respectively, and the agreement rate between the indirect ELISA and one commercialization ELISA kit was 95.6%; compared with the ELISA coated with NS1 protein, the agreement ratio was 97.7%; meanwhile, the positive rate of the indirect ELISA was apparently higher than the results of latex agglutination test (LAT). All these indicated that the indirect ELISA is not only sensitive and specific, but also suitable for large-scale seroepidemiological investigation for porcine Japanese encephalitis.