N-Cap RNA: protected RNAs for in-tube diagnostic controls and inter-laboratory standards

用于诊断或筛选目的的来自粗样品的RNA扩增在分离、净化和扩增过程期间的许多阶段可能失败。这种失败会产生假阴性结果，这在筛选关键样品时是不可接受的，例如在动物或人类流行性病毒性疾病爆发期间。因此，如果不是必需的，也非常希望在过程中尽可能早的步骤中包括对照RNA，以便阳性对照信号可以验证从样品采集到最终扩增和检测的每个步骤。然而，RNA是一种脆弱的分子，并且未受保护的RNA标准品非常迅速地降解。我们已经表明，这种降解可以通过将RNA封装在植物病毒颗粒（N-cap RNA）内来防止，并且，此外，这种颗粒可以充当高效的管内对照。我们现在需要开发快速生产用于广泛目标疾病的此类控制的方法。

Amplification of RNA from crude samples for diagnostic or screening purposes can fail at many stages during the isolation, clean-up and amplification processes. Such failures produce false negative results, which are not acceptable when screening critical samples, for instance during outbreaks of epidemic viral disease in animals or humans. It is therefore highly desirable, if not essential, to include control RNA at the earliest possible step in the process, so that a positive control signal can validate every step from sample acquisition to final amplification and detection. However RNA is a fragile molecule and an unprotected RNA standard is very rapidly degraded. We have shown that this degradation can be prevented by encapsulating the RNA within a plant virus particle (N-cap RNA) and, furthermore, that such particles can act as highly effective in-tube controls. We now need to develop methods for the rapid production of such controls for a wide range of target diseases.