Haley Nicholas J, Carver Scott, Hoon-Hanks Laura L, Henderson Davin M, Davenport Kristen A, Bunting Elizabeth, Gray Shawn, Trindle Bruce, Galeota Judith, LeVan Ivy, Dubovos Tracy, Shelton Paul, Hoover Edward A
Prion Research Center, Department of Microbiology, Immunology, and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, USA
School of Biological Sciences, University of Tasmania, Hobart, Tasmania, Australia.
J Clin Microbiol. 2014 Sep;52(9):3237-43. doi: 10.1128/JCM.01258-14. Epub 2014 Jun 23.
Chronic wasting disease (CWD), a transmissible spongiform encephalopathy of deer, elk, and moose, is the only prion disease affecting free-ranging animals. Since the disease was first identified in northern Colorado and southern Wyoming in 1967, new epidemic foci of the disease have been identified in 20 additional states, as well as two Canadian provinces and the Republic of South Korea. Identification of CWD-affected animals currently requires postmortem analysis of brain or lymphoid tissues using immunohistochemistry (IHC) or an enzyme-linked immunosorbent assay (ELISA), with no practical way to evaluate potential strain types or to investigate the epidemiology of existing or novel foci of disease. Using a standardized real-time (RT)-quaking-induced conversion (QuIC) assay, a seeded amplification assay employing recombinant prion protein as a conversion substrate and thioflavin T (ThT) as an amyloid-binding fluorophore, we analyzed, in a blinded manner, 1,243 retropharyngeal lymph node samples from white-tailed deer, mule deer, and moose, collected in the field from areas with current or historic CWD endemicity. RT-QuIC results were then compared with those obtained by conventional IHC and ELISA, and amplification metrics using ThT and thioflavin S were examined in relation to the clinical history of the sampled deer. The results indicate that RT-QuIC is useful for both identifying CWD-infected animals and facilitating epidemiological studies in areas in which CWD is endemic or not endemic.
慢性消耗病（CWD）是鹿、麋鹿和驼鹿的一种传染性海绵状脑病，是唯一影响自由放养动物的朊病毒病。自1967年该病在科罗拉多州北部和怀俄明州南部首次被发现以来，在另外20个州以及加拿大的两个省和韩国又发现了新的疫病流行区。目前，识别受CWD感染的动物需要使用免疫组织化学（IHC）或酶联免疫吸附测定（ELISA）对脑或淋巴组织进行死后分析，尚无实用方法来评估潜在的毒株类型或调查现有或新出现的疫病流行区的流行病学情况。我们使用标准化的实时（RT）-颤抖诱导转化（QuIC）测定法，这是一种以重组朊病毒蛋白作为转化底物、硫黄素T（ThT）作为淀粉样蛋白结合荧光团的种子扩增测定法，以盲法分析了从当前或历史上存在CWD地方病的地区野外采集的1243份白尾鹿、骡鹿和驼鹿的咽后淋巴结样本。然后将RT-QuIC结果与通过传统IHC和ELISA获得的结果进行比较，并根据采样鹿的临床病史检查使用ThT和硫黄素S的扩增指标。结果表明，RT-QuIC对于识别受CWD感染的动物以及促进CWD地方病流行区或非流行区的流行病学研究均有用处。
