Welch Ryan J, Anderson Brian L, Litwin Christine M
Associated Regional and University Pathologists (ARUP) Institute for Clinical and Experimental Pathology, Salt Lake City, UT, USA.
Department of Pathology, University of Utah, Salt Lake City, UT, USA.
J Med Microbiol. 2009 Jun;58(Pt 6):806-810. doi: 10.1099/jmm.0.006064-0.
The envelope glycoprotein G of rabies virus in vaccines induces the production of neutralizing antibodies important in the protection against the disease. The measurement of anti-envelope glycoprotein antibodies is a good predictor of the degree of humoral immunity in people during anti-rabies treatment or after vaccination. Several assays exist for the serological determination of antibody protection against rabies virus infection. Antibody neutralization by the rapid fluorescent focus inhibition test (RFFIT) or the fluorescent antibody virus neutralization (FAVN) test is currently the gold standard. Performance of the highly complex RFFIT and FAVN tests, however, requires specialized reference laboratories with expertise with this assay. Although not widely used, ELISA test kits are available and may be an additional option for testing that is more accessible. The aim of the present study was to evaluate available ELISA assays for the determination of anti-rabies antibodies. We compared the Bio-Rad Platelia Rabies II ELISA, DRG Rabies Virus IgG Ab ELISA and Focus Diagnostics Rabies Antibody Detection by ELISA to RFFIT. Bland-Altman plots comparing the Bio-Rad Platelia assay and the Focus Diagnostics assay to RFFIT showed a low degree of variability between the ELISA assays and RFFIT results except in samples with high RFFIT values. The agreement, sensitivity and specificity of Bio-Rad Platelia Rabies II ELISA when compared to RFFIT were 95.1 %, 94.1 % and 95.8 %, respectively. The DRG Rabies assay compared to RFFIT had an agreement of 77.7 %, a sensitivity of 86.7 % and a specificity of 69.4 %. The agreement, sensitivity and specificity of Focus Diagnostics Rabies Detection by ELISA when compared to RFFIT were 82.2 %, 91.7 % and 73.0 %, respectively. Overall, the Bio-Rad Platelia assay showed higher accuracy and specificity than either the DRG or Focus assays. All of these ELISAs, however, measure all antibody types and do not discriminate the neutralizing antibodies as measured by functional assays (RFFIT and FAVN) and cannot be relied upon to predict the neutralizing activity of the sera. The results of this study offer insight into the availability of alternative, less-complex methods to monitor rabies antibody titres in at-risk individuals following vaccination.
疫苗中狂犬病病毒的包膜糖蛋白G可诱导产生对预防该疾病至关重要的中和抗体。抗包膜糖蛋白抗体的检测是抗狂犬病治疗期间或接种疫苗后人体体液免疫程度的良好预测指标。现有几种用于血清学检测抗狂犬病病毒感染抗体保护作用的检测方法。目前，通过快速荧光灶抑制试验（RFFIT）或荧光抗体病毒中和试验（FAVN）进行抗体中和检测是金标准。然而，高度复杂的RFFIT和FAVN检测需要具备该检测专业知识的专门参考实验室。酶联免疫吸附测定（ELISA）检测试剂盒虽未广泛使用，但有产品可供选择，可能是一种更易获得的检测额外选项。本研究的目的是评估用于测定抗狂犬病抗体的现有ELISA检测方法。我们将伯乐公司的狂犬病Ⅱ型ELISA试剂盒、DRG狂犬病病毒IgG抗体ELISA试剂盒以及Focus诊断公司的ELISA狂犬病抗体检测试剂盒与RFFIT进行了比较。将伯乐公司的检测方法和Focus诊断公司的检测方法与RFFIT进行比较的布兰德 - 奥特曼图显示，除了RFFIT值较高的样本外，ELISA检测方法与RFFIT结果之间的变异性较低。与RFFIT相比，伯乐公司狂犬病Ⅱ型ELISA试剂盒的一致性、敏感性和特异性分别为95.1%、94.1%和95.8%。与RFFIT相比，DRG狂犬病检测试剂盒的一致性为77.7%，敏感性为86.7%，特异性为69.4%。与RFFIT相比，Focus诊断公司的ELISA狂犬病检测试剂盒的一致性、敏感性和特异性分别为82.2%、91.7%和73.0%。总体而言，伯乐公司的检测方法比DRG或Focus诊断公司的检测方法具有更高的准确性和特异性。然而，所有这些ELISA检测方法均检测所有抗体类型，无法像功能检测（RFFIT和FAVN）那样区分中和抗体，并不能用于预测血清的中和活性。本研究结果为监测高危个体接种疫苗后狂犬病抗体滴度的替代、不太复杂的方法的可用性提供了见解。
