Development of Diagnostic Method for Unconventional Agent (Scrapie Gagent) Infection.

研究了绵羊淋巴网状器官中由瘙痒病相关纤维组成的蛋白质(PrP)作为诊断工具的有效性。用兔抗羊PrP多克隆抗体进行免疫印迹分析。在6只表现出自然瘙痒病临床症状的绵羊中，有5只羊的中枢神经系统样本、4只绵羊的脾样本和3只绵羊的淋巴样本中检测到了PRP。在六只临床和组织病理学异常的绵羊中，一只羊的脾和淋巴结样本中检测到PRP，而在中枢神经系统样本中未检测到PRP。这只动物似乎处于疾病的早期临床阶段。对47只临床正常的绵羊进行了PrP的检测。在47只绵羊中有3只的脾样本中检测到了这种病毒，在37只被测试的绵羊中有3只的淋巴样本中检测到了这种病毒。同样，在接种14个月后，从三只实验感染的绵羊中的一只手术获得的淋巴样本中也检测到PrP。PrP阳性的绵羊和剩余的一只PrP阴性的绵羊分别在6个月和5个月后出现了瘙痒的临床症状。实验感染18个月后处死的1只绵羊中枢神经系统、脾和淋巴结中PrP呈阳性，而感染后2、8、16、18和21个月处死或死亡的5只绵羊PrP检测均为阴性或可疑。

The usefulness of detecting the protein (PrP) consisting of scrapie-associated fibrils in the lymphoreticular organs of sheep as a diagnostic tool was investigated. The PrP was detected by means of a rabbit-anti-sheep PrP polyclonal antibody by Western blot analysis. PrP was detected in samples from the central nervous system of five of six sheep showing clinical signs of natural scrapie infection, in spleen samples from four of the six sheep and in lymph node samples taken from three of the sheep. PrP was detected in the spleen and lymph node samples, but not in the central nervous system samples from one of the six sheep that was clinically and histopathologically abnormal. This animal appeared to be in the early clinical stage of the disease. A total of 47 clinically normal sheep were examined for the presence of PrP. It was detected in spleen samples from three of the 47 sheep and in lymph node samples from three of the 37 sheep tested. Similarly, PrP was detected in a samples of lymph node obtained surgically from one of three experimentally infected sheep 14 months after inoculation. The PrP-positive sheep and one of the remaining PrP-negative sheep showed clinical signs of scrapie six and five months later respectively. One sheep sacrificed 18 months after experimental infection was positive for PrP in the central nervous system, spleen and lymph node, but five other sheep which were sacrificed or died two, eight, 16, 18 and 21 months after infection were negative or doubtful for the detection of PrP.