Guiroy D C, Marsh R F, Yanagihara R, Gajdusek D C
Laboratory of Central Nervous System Studies, National Institute of Neurological Disorders and Stroke, National Institute of Health, Bethesda, MD 20892.
Neurosci Lett. 1993 May 28;155(1):112-5. doi: 10.1016/0304-3940(93)90685-e.
Transmissible mink encephalopathy (TME), a naturally occurring subacute spongiform encephalopathy in commercially ranch-reared mink (Mustela vision), is characterized neuropathologically by spongiform changes in the neuropil, intracytoplasmic neuronal vacuolation and astrocytic hypertrophy and hyperplasia. Amyloid deposits have not been observed in brain tissue sections from animals with natural and experimental TME using conventional histochemical stains such as Congo red. To determine if amyloid deposits be visualized by immunocytochemical techniques, we stained formalin-fixed, formic acid-treated brain tissue sections from several animal species with natural and experimental TME, using a rabbit antiserum directed against scrapie amyloid (PrP27-30). Scrapie amyloid-immunoreactive deposits were found in golden Syrian hamsters experimentally infected with TME, but were absent in mink with natural and experimental TME, as well as in ferrets and squirrel monkeys with experimental TME. The scrapie amyloid-immunoreactive deposits, which were non-congophilic and non-birefringent, were distributed in the subependymal, subpial and perivascular regions of the brain, as in hamsters infected with the 263K strain of scrapie. Ultrastructurally, scrapie amyloid-immunoreactive deposits revealed a collection of degenerating neurites with numerous abnormal mitochondria and degenerating synapses. Amyloid fibrils were not observed. Anti-scrapie amyloid antibodies immunoabsorbed with scrapie amyloid abolished immunostaining. Our data indicate the presence of scrapie amyloid lacking the molecular conformation of amyloid fibrils in hamsters with experimental TME.
可传播水貂脑病（TME）是一种在商业养殖水貂（鼬属）中自然发生的亚急性海绵状脑病，其神经病理学特征为神经毡出现海绵状变化、胞浆内神经元空泡形成以及星形细胞肥大和增生。使用刚果红等传统组织化学染色方法，在患有自然和实验性TME的动物脑组织切片中未观察到淀粉样沉积物。为了确定是否可以通过免疫细胞化学技术观察到淀粉样沉积物，我们使用针对瘙痒病淀粉样蛋白（PrP27 - 30）的兔抗血清，对来自几种患有自然和实验性TME的动物物种的经福尔马林固定、甲酸处理的脑组织切片进行染色。在实验感染TME的金黄仓鼠中发现了瘙痒病淀粉样蛋白免疫反应性沉积物，但在患有自然和实验性TME的水貂以及患有实验性TME的雪貂和松鼠猴中未发现。这些瘙痒病淀粉样蛋白免疫反应性沉积物不具有刚果红亲和性和双折射性，分布在脑的室管膜下、软脑膜下和血管周围区域，与感染263K株瘙痒病的仓鼠情况相同。在超微结构上，瘙痒病淀粉样蛋白免疫反应性沉积物显示为一组退化的神经突，伴有大量异常线粒体和退化的突触。未观察到淀粉样纤维。用瘙痒病淀粉样蛋白免疫吸附的抗瘙痒病淀粉样蛋白抗体消除了免疫染色。我们的数据表明，在患有实验性TME的仓鼠中存在缺乏淀粉样纤维分子构象的瘙痒病淀粉样蛋白。
