PMCA Detection of CWD Infection in Cervid and Non-Cervid Species

描述（由申请人提供）：慢性消耗性疾病（CWD）是一种紧急的、有效传播的、致命的鹿（鹿、麋鹿、驼鹿）朊病毒疾病，目前在15个州、2个加拿大省和韩国发现。我们发现，能够传播慢性消耗病的传染性朊病毒存在于慢性消耗病感染鹿的唾液、血液和尿液中，这可能解释了疾病的横向传播。CWD朊病毒在唾液和血液中的存在证实了朊病毒在生物液体中的感染性，并通过更灵敏的体外试验为死前检测提供了现实的希望，这构成了该应用的基础。直接检测的异常CWD朊病毒蛋白（PrPRES/CWD）的体液或排泄物的鹿一直不可能使用当代的检测方法（即免疫组织化学，蛋白质印迹，ELISA）。在这里，我们建议采用系列蛋白质错误折叠循环扩增（sPMCA）扩增和检测PrPCWD在唾液，血液，尿液和粪便中的感染鹿。PrPCWD的直接体外检测将使症状前的死前诊断，提高对慢性消耗病的生态学理解，并可能使朊病毒携带状态和鹿产品污染的检测成为可能。自然界中是否存在CWD感染的非宫颈储库尚不清楚。同样，慢性消耗病是否对人类健康构成风险也不确定。为了开始评估慢性消耗病跨物种传播的可能性，我们建议使用sPMCA作为替代品，以评估暴露于慢性消耗病朊病毒后，来自选定的非鹿科动物物种的正常朊病毒蛋白是否可以转化为异常的PrPCWD亚型。这些信息将用于指导相关的体内接种和流行病学研究，以评估CWD物种屏障，确定自然界中潜在的储存宿主，并更好地估计CWD对人类或其他物种造成的潜在健康风险。 公共卫生相关性：慢性消耗性疾病（CWD）是一种迅速传播的致命性朊病毒疾病，鹿和麋鹿，可能通过唾液传播，现在在15个州。慢性消耗病是否对人类健康构成类似疯牛病的风险尚不清楚。这里提出了一种更强大的新测试，用于检测受感染鹿的唾液、血液和排泄物中的CWD朊病毒--这在当前技术下是不可能的，但对于控制CWD在鹿和潜在其他物种中的传播至关重要。

DESCRIPTION (provided by applicant): Chronic wasting disease (CWD), an emergent, efficiently transmitted, fatal prion disease of cervids (deer, elk, moose), is now identified in 15 states, 2 Canadian provinces, and Korea. We have found that infectious prions capable of transmitting CWD are present in the saliva, blood, and urine of CWD-infected deer, potentially explaining the lateral transmission of the disease. The presence of CWD prions in saliva and blood confirms prion infectivity in biological fluids and provides realistic hope for antemortem detection via a more sensitive in vitro assay, which forms the basis for this application. Direct detection of the abnormal CWD prion protein (PrPRES/CWD) in body fluids or excreta of deer has not been possible using contemporary assay methodologies (i.e. immunohistochemistry, western blotting, ELISA). Here we propose to employ serial protein misfolding cyclic amplification (sPMCA) to amplify and detect PrPCWD in saliva, blood, urine, and feces of infected deer. Direct in vitro detection of PrPCWD would enable pre-symptomatic ante-mortem diagnosis, improve ecologic understanding of CWD, and potentially enable detection of prion carrier states and contamination in cervid products. Whether a non-cervid reservoir for CWD infection exists in nature remains unknown. Likewise, whether CWD represents a risk to human health is uncertain. To begin to assess the potential for trans-species transmission of CWD, we propose to use sPMCA as a surrogate to assess whether the normal prion protein from selected non-cervid species can be converted to the abnormal PrPCWD isoform after exposure to CWD prions. This information will be used to direct correlative in vivo inoculation and epidemiologic studies needed to assess the CWD species barrier, identify potential reservoir hosts in nature, and better estimate potential human or other species health risks posed by CWD. PUBLIC HEALTH RELEVANCE: Chronic wasting disease (CWD) is a rapidly spreading fatal prion disease of deer and elk, probably spread through saliva, and now present in 15 states. Whether CWD may represent a risk to human health analogous to mad cow disease is unknown. Proposed here is a new more powerful test to detect CWD prions in saliva, blood, and excretions of infected deer-something not possible with current technology yet vital to controlling the spread of CWD among deer and potentially other species.