A viral pseudotype based approach to measuring morbillivirus neutralising antibodies

该项目的目标是开发一种快速、敏感和特异的诊断测试。这项测试将用于诊断一种名为小反刍兽疫的绵羊和山羊病毒感染。小反刍兽疫对全世界畜牧业构成威胁，已被宣布为全球控制和通过疫苗接种根除的优先目标。小反刍兽疫病毒全球控制和疫苗接种规划的成功将需要提供一种高度准确和快速的诊断测试，这种测试不需要昂贵的专门实验室控制设施，因为它必须在世界各地的实验室进行。然而，目前规定的PPRV测试是活病毒中和测试，这种测试速度很慢，需要在高度生物控制的实验室中操作，而且灵敏度和灵活性都有限。为了开发一种改进的PPRV诊断检测方法，我们采用了一种技术，将PPRV表面糖蛋白表达在源自水疱性口炎病毒（VSV）的无害载体病毒上，生成VSV（PPRV）“假型”。病毒假型由一种病毒（在本例中为VSV）的结构蛋白和遗传物质组成，携带另一种不同病毒的表面蛋白（在本试验中我们使用PPRV H和F蛋白）。VSV（PPRV）假型可用于比传统活病毒试验更快地测量PPRV特异性抗体（3天相比1至2周）。该试验显示出比活病毒试验更高的灵敏度（至少10倍以上的灵敏度），并且可以测量抗体对不同病毒株的反应，这些病毒株代表着不同的病毒谱系。最后，该试验绕过了对高水平生物防护的要求，可以在世界上任何具有基本细胞培养设施的实验室安全地进行。在这个项目中，我们将通过生成一种基于VSV（PPRV）的诊断测试来协助世界动物卫生组织的PPRV全球控制和根除计划。通过这项测试，我们将能够确定受感染的动物，并调查可能负责将该病毒传播给牲畜的野生动物种群。这一信息将有助于确保疫苗接种规划针对传播风险高的地区的易感人群，从而提高成功根除PPRV的机会。

The goal of this project is to develop a diagnostic test that is rapid, sensitive and specific. This test will be used to diagnose a viral infection of sheep and goats called PPR, or peste des petits ruminants. PPR is a threat to the livestock industry worldwide and has been declared a priority target for global control and eradication by vaccination. The success of a global control and vaccination programme against peste des petits ruminants virus (PPRV) will require the availability of a highly accurate and rapid diagnostic test that can be performed without the need for expensive specialized laboratory containment facilities since it will have to be carried out in laboratories across the world. However, the current prescribed test for PPRV is the live virus neutralisation test, a test that is slow, requires a laboratory operating under a high level of biocontainment, and is limited in both sensitivity and flexibility. In order to develop an improved PPRV diagnostic test, we have used a technique in which PPRV surface glycoproteins are expressed on a harmless carrier virus derived from vesicular stomatitis virus (VSV) to generate VSV(PPRV) "pseudotypes". A viral pseudotype consists of the structural proteins and genetic material of one virus (in this case VSV), carrying the surface proteins of another, different virus (in this assay we use the PPRV H and F proteins). The VSV(PPRV) pseudotypes can be used to measure PPRV specific antibodies more rapidly than conventional live virus tests (three days compared with 1 to 2 weeks). The assay displays greater sensitivity (at least 10-times more sensitive) than live virus tests and can measure antibody responses against diverse strains of virus representative of distinct viral lineages in circulation. Finally, the assay circumvents the requirement for high level biocontainment and may be performed safely in any laboratory worldwide with basic cell culture facilities.In this project we will assist the World Animal Health Organization's Global Control and Eradication program for PPRV by generating a VSV(PPRV)-based diagnostic test. With this test, we will be able to identify infected animals and investigate populations of wild animals which may be responsible for transmitting this virus to livestock. This information will help ensure that vaccination programmes target susceptible populations in areas with a high risk of transmission and therefore improve the chances of successfully eradicating PPRV.