College of Veterinary Medicine, Qingdao Agricultural University, Qingdao, China.
Front Cell Infect Microbiol. 2022 Sep 26;12:1024690. doi: 10.3389/fcimb.2022.1024690. eCollection 2022.
Humans are exposed to infection as pet cats gradually become family members and represent an increasing public health risk worldwide. Toxoplasmosis diagnosis constitutes an important measure for disease prevention and control. In this study, real-time fluorescence quantitative loop-mediated isothermal amplification (qLAMP) and visual LAMP detection technologies were established to conduct tests of based on the membrane DNA extraction method, and the optimal detection mix was determined by adding the protective reagent trehalose and screening the concentrations of Mg and dNTPs. Paraffin and lyophilization were used to reduce and even remove aerosol pollution, constructing a detailed anti-contamination protocol. Based on the positive standard plasmid DNA, the LODs of qLAMP and visual LAMP were 92 copies/μL and 92 copies/μL, and the standard curve of qLAMP was Y=2.9503X+20.8992 with R 0.99. The applicability of the qLAMP and visual LAMP assays in disease diagnosis was assessed by evaluating 200 clinical cat faeces samples. The assays showed good diagnostic consistency, with kappa values of 1.0 and 0.99 compared with Man qPCR, respectively. Compared with Man qPCR, the diagnostic specificity/sensitivity of qLAMP and visual LAMP were 100%/100% and 100%/80%, respectively. The qLAMP and visual LAMP assays reported here are rapid and simple tests without extensive sample preparation and have a short turnaround time within 60 min, making them suitable for point-of-care testing.
人类暴露于感染,因为宠物猫逐渐成为家庭成员,代表着全球日益增长的公共卫生风险。弓形虫病的诊断是疾病预防和控制的重要措施。在这项研究中,建立了基于膜 DNA 提取方法的实时荧光定量环介导等温扩增(qLAMP)和目视 LAMP 检测技术,并通过添加保护剂海藻糖和筛选 Mg 和 dNTPs 的浓度来确定最佳检测混合物。使用石蜡和冻干来减少甚至消除气溶胶污染,构建了详细的防污染方案。基于阳性标准质粒 DNA,qLAMP 和目视 LAMP 的 LODs 分别为 92 拷贝/μL 和 92 拷贝/μL,qLAMP 的标准曲线为 Y=2.9503X+20.8992,R 为 0.99。通过评估 200 份临床猫粪便样本,评估了 qLAMP 和目视 LAMP 检测方法在疾病诊断中的适用性。这些检测方法显示出良好的诊断一致性,与 Man qPCR 相比,kappa 值分别为 1.0 和 0.99。与 Man qPCR 相比,qLAMP 和目视 LAMP 的诊断特异性/敏感性分别为 100%/100%和 100%/80%。本研究报道的 qLAMP 和目视 LAMP 检测方法快速简单,无需广泛的样本制备,且在 60 分钟内即可获得检测结果,非常适合现场即时检测。