National Centre for Foreign Animal Disease, Canadian Food Inspection Agency, Winnipeg, MB, Canada.
Department of Microbiology, Immunology, faculty of Medicine, Université Laval, Québec, QC, Canada.
Transbound Emerg Dis. 2018 Feb;65(1):77-84. doi: 10.1111/tbed.12606. Epub 2017 Mar 27.
Ebolaviruses (family Filoviridae, order Mononegavirales) cause often fatal, haemorrhagic fever in primates including humans. Pigs have been identified as a species susceptible to Reston ebolavirus (RESTV) infection, with indicated transmission to humans in the Philippines; however, their role during Ebola outbreaks in Africa needs to be clarified. To perform surveillance studies, detection of ebolavirus requires a prerequisite validation of viral RNA and antibody detection methods in swine samples. These diagnostic tests also need to be suitable for deployment to low-level containment laboratories. In this study, we developed a set of tests for detection of antibodies against Zaire ebolavirus (EBOV) in swine. Recombinant EBOV nucleoprotein was produced using a baculovirus expression system for indirect ELISA development. Evaluation of this assay was performed using laboratory and field samples, achieving a diagnostic specificity of 99%. Importantly, the indirect ELISA was able to detect antibodies to EBOV at 7 dpi, 3 days earlier than virus neutralization tests (VNT). The format of the VNT in this work was modified to a microtitre plaque reduction neutralization assay (miPRNT) complemented with immunostaining to provide a more rapid and highly specific assay. Finally, a confirmatory immunoblot assay was generated to supplement the indirect ELISA results.
埃博拉病毒（丝状病毒科，单股负链病毒目）可引起包括人类在内的灵长类动物的致命性出血热。猪已被确定为易感染雷斯顿埃博拉病毒（RESTV）的物种，在菲律宾有向人类传播的迹象；然而，它们在非洲埃博拉疫情中的作用仍需澄清。为了开展监测研究，在猪样本中检测埃博拉病毒需要预先验证病毒 RNA 和抗体检测方法。这些诊断测试也需要适合部署到低水平隔离实验室。在这项研究中，我们开发了一套用于检测猪中针对扎伊尔埃博拉病毒（EBOV）的抗体的检测方法。使用杆状病毒表达系统生产重组 EBOV 核蛋白，用于间接 ELISA 的开发。使用实验室和现场样本对该检测方法进行了评估，获得了 99%的诊断特异性。重要的是，间接 ELISA 能够在 7dpi（感染后第 7 天）检测到针对 EBOV 的抗体，比病毒中和试验（VNT）早 3 天。这项工作中的 VNT 格式被修改为微滴定噬斑减少中和试验（miPRNT），并辅以免疫染色，以提供更快速和高度特异性的检测方法。最后，生成了确认免疫印迹检测方法来补充间接 ELISA 的结果。
