National Reference Laboratory of TSEs (CEA), Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d'Aosta, Turin, Italy.
Dipartimento di Scienze Veterinarie, Sezione Clinica Medica, University of Turin, Grugliasco, Turin, Italy.
Sci Rep. 2019 Apr 16;9(1):6173. doi: 10.1038/s41598-019-42449-7.
Since 2005, two cases of natural bovine spongiform encephalopathies (BSE) have been reported in goats. Furthermore, experimental transmissions of classical (C-BSE) and atypical (L-BSE) forms of BSE in goats were also reported. To minimize further spreading of prion diseases in small ruminants the development of a highly sensitive and specific test for ante-mortem detection of infected animals would be of great value. Recent studies reported high diagnostic value of a second generation of cerebrospinal fluid (CSF) Real-Time Quaking-Induced Conversion (RT-QuIC) assay across a wide spectrum of human prions. Here, we applied this improved QuIC (IQ-CSF) for highly efficient detection of TSEs prion protein in goat cerebrospinal fluid. IQ-CSF sensitivity and specificity were evaluated on CSF samples collected at disease endpoint from goats naturally and experimentally infected with scrapie or bovine isolates of C-BSE and L-BSE, respectively. Next, CSF samples collected from L-BSE infected goats during pre-symptomatic stage were also analysed. PrP associated seeding activity was detected at early time points after experimental inoculation, with an average time of 439 days before clinical symptoms appeared. Taken together these data are indicative of the great potential of this in vitro prion amplification assay as ante-mortem TSE test for live and asymptomatic small ruminants.
自 2005 年以来，已经在山羊中报告了两例天然牛海绵状脑病（BSE）病例。此外，还报告了经典（C-BSE）和非典型（L-BSE）形式的 BSE 在山羊中的实验传播。为了最大限度地减少小反刍动物朊病毒病的进一步传播，开发一种高度敏感和特异的用于感染动物生前检测的方法将具有重要价值。最近的研究报告称，第二代脑脊液（CSF）实时震颤诱导转化（RT-QuIC）检测在广泛的人类朊病毒中具有很高的诊断价值。在这里，我们应用了这种改进的 QuIC（IQ-CSF）来高效地检测山羊脑脊液中的 TSE 朊病毒蛋白。在疾病终点时从自然和实验感染羊瘙痒病或牛 C-BSE 和 L-BSE 分离株的山羊 CSF 样本中评估了 IQ-CSF 的敏感性和特异性。接下来，还分析了在潜伏期感染 L-BSE 的山羊的 CSF 样本。在实验接种后早期时间点检测到与 PrP 相关的种子活性，平均在出现临床症状前 439 天。这些数据表明，这种体外朊病毒扩增检测作为活的和无症状的小反刍动物的生前 TSE 检测具有巨大的潜力。
