Zhuo Xunhui, Sun Hongchao, Zhang Zhi, Luo Jiaqing, Shan Ying, Du Aifang
* Institute of Preventive Veterinary Medicine, Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, College of Animal Sciences, Zhejiang University, Hangzhou 310058, China.
J Parasitol. 2017 Jun;103(3):237-242. doi: 10.1645/16-89. Epub 2017 Mar 23.
Serologic tests are widely accepted and applied as means to detect anti- Toxoplasma gondii immunoglobulin G antibodies. In this study, recombinant matrix antigen (rMAG1) was induced by isopropyl-β-d-thiogalactoside and purified by nickel-nitrilotriacetic acid purification system. We then developed and optimized an indirect enzyme-linked immunosorbent assay (ELISA) through checkerboard assays using serial dilutions of antigens and sera to assess the potential use of rMAG1 in serologic detection of T. gondii infection in dogs. Serum samples from 93 domestic dogs were analyzed by western blot and rMAG1-ELISA. The results were compared with those obtained from an ELISA with the soluble Toxoplasma lysate antigens (TLA). We found that although yielding an excellent agreement (96.7%) with western blot data (κ = 0.9659), rMAG1-ELISA produced higher sensitivity (93.9% vs. 87.8%) and specificity (98.3% vs. 96.7%) than TLA-ELISA. In addition, receiver operating characteristic analysis also revealed that rMAG1-ELISA is in more agreement with western blot (area under the curve [AUC] = 0.985) relative to TLA-ELISA (AUC = 0.955). These results indicated that the rMAG1-ELISA established in this study provides a promising and reliable tool for serologic detection of T. gondii infection in dogs.
血清学检测作为检测抗弓形虫免疫球蛋白G抗体的手段已被广泛接受和应用。在本研究中，重组基质抗原（rMAG1）通过异丙基-β-D-硫代半乳糖苷诱导表达，并经镍-次氮基三乙酸纯化系统纯化。然后，我们通过棋盘滴定法，使用抗原和血清的系列稀释液，开发并优化了一种间接酶联免疫吸附测定（ELISA），以评估rMAG1在犬弓形虫感染血清学检测中的潜在用途。采用蛋白质印迹法和rMAG1-ELISA对93只家犬的血清样本进行分析。将结果与可溶性弓形虫裂解物抗原（TLA）ELISA的结果进行比较。我们发现，尽管rMAG1-ELISA与蛋白质印迹数据一致性极佳（96.7%）（κ = 0.9659），但与TLA-ELISA相比，rMAG1-ELISA具有更高的敏感性（93.9%对87.8%）和特异性（98.3%对96.7%）。此外，受试者工作特征分析还显示，相对于TLA-ELISA（曲线下面积[AUC] = 0.955），rMAG1-ELISA与蛋白质印迹的一致性更高（AUC = 0.985）。这些结果表明，本研究建立的rMAG1-ELISA为犬弓形虫感染的血清学检测提供了一种有前景且可靠的工具。
