Gu Yi, Wang Zedong, Cai Yufeng, Li Xiaoxing, Wei Feng, Shang Limin, Li Jiping, Liu Quan
Military Veterinary Institute, Academy of Military Medical Sciences, Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Changchun, Jilin Province, People's Republic of China (Gu, Wang, Shang, Li, Liu)College of Life Science, Jilin Agricultural University, Changchun, Jilin Province, People's Republic of China (Cai, Li, Wei).
Military Veterinary Institute, Academy of Military Medical Sciences, Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Changchun, Jilin Province, People's Republic of China (Gu, Wang, Shang, Li, Liu)College of Life Science, Jilin Agricultural University, Changchun, Jilin Province, People's Republic of China (Cai, Li, Wei)
J Vet Diagn Invest. 2015 Sep;27(5):616-20. doi: 10.1177/1040638715596033. Epub 2015 Jul 21.
Toxoplasma gondii can infect almost all warm-blooded animals, and many serological methods have been developed to detect T. gondii infection in a variety of animal species. In the present study, the seroprevalence of T. gondii infection in farmed mink in northeast China was determined using the modified agglutination test (MAT), a Western blot (WB), and 3 enzyme-linked immunosorbent assays (ELISAs) with protein A/G conjugate, using either of 2 recombinant dense granule antigens, GRA1 and GRA7, or Toxoplasma soluble antigens (TSA). There was no significant difference between the detection results of the GRA1-, GRA7-, and TSA-ELISAs and WB (McNemar chi-square, P > 0.05), but a significant difference was observed between MAT and WB (P < 0.05). A near perfect agreement (97.0%) was found between the GRA7-ELISA and WB (κ = 0.83), and a substantial agreement (92.4-93.1%) was observed in the TSA- and GRA1-ELISAs (κ = 0.68-0.73). The GRA7-ELISA showed the highest sensitivity and specificity, and the lowest false-positive and negative rates, while the MAT gave both a low sensitivity and frequent false positives in comparison to the WB. Receiver operating characteristic analysis revealed the largest area under curve of 0.85 (95% confidence interval: 0.74-0.96), and the highest relative sensitivity (72.7%) and specificity (99.0%) for a cutoff value of 0.19 in the GRA7-ELISA. These results indicate that the GRA7-ELISA is suitable for detection of T. gondii infection in mink and that MAT should be used with caution.
刚地弓形虫可感染几乎所有温血动物，人们已研发出多种血清学方法来检测多种动物物种中的刚地弓形虫感染情况。在本研究中，采用改良凝集试验（MAT）、蛋白质印迹法（WB）以及3种使用蛋白A/G缀合物的酶联免疫吸附测定（ELISA），分别使用2种重组致密颗粒抗原GRA1和GRA7或弓形虫可溶性抗原（TSA），来测定中国东北地区养殖水貂的刚地弓形虫感染血清阳性率。GRA1-ELISA、GRA7-ELISA和TSA-ELISA与WB的检测结果之间无显著差异（McNemar卡方检验，P>0.05），但MAT与WB之间存在显著差异（P<0.05）。GRA7-ELISA与WB之间发现了近乎完美的一致性（97.0%）（κ=0.83），TSA-ELISA和GRA1-ELISA观察到高度一致性（92.4%-93.1%）（κ=0.68-0.73）。GRA7-ELISA显示出最高的敏感性和特异性，以及最低的假阳性和假阴性率，而与WB相比，MAT的敏感性较低且假阳性频繁。受试者工作特征分析显示，GRA7-ELISA在截断值为0.19时曲线下面积最大，为0.85（95%置信区间：0.74-0.96），相对敏感性最高（72.7%），特异性最高（99.0%）。这些结果表明，GRA7-ELISA适用于检测水貂中的刚地弓形虫感染，MAT应谨慎使用。
