Norris F H
Neurol Neurocir Psiquiatr. 1977;18(2-3 Suppl):443-54.
Clinicians have noted resemblance between ALS with predominantly lower motor involvement and a chronic type of poliomyelitis. Occasional cases of ALS show lymphocytic infiltrations in the neuropathology. Cytoplasmic inclusion bodies as well as possible transmission of ALS to the monkey, were noted by Soviet investigators. Major questions about the latter remain, but inclusion bodies have been seen in cases outside the USSR, and search for a virus has been pursued. So far, efforts at culture, including the technique of co-cultivation, have not been successful in 3 different laboratories using material from ALS autopsied within 2 hours of death. Nor has such material and specimens from other cases produced transmissible disease in animals of laboratories where kuru, Jakob's disease and SSPE have been transmitted. Study of serum antibodies has also been negative. These negative culture, transmission and antibody studies do not exclude a viral etiology: in kuru, for example, many years passed before transmission was demonstrated, which remains the only evidence of kuru's infectivity. Evidence of an immunologic disorder in ALS has been obtained from kidney biopsies, the lack of any clinical benefit from immunosuppression may indicate that the kidney finding reveals a response to infection, though whether viral or even relevant is unknown. Two recent ALS cases will be illustrated in which virus-like particles were demonstrated post mortem by electronmicroscopy. In one, myxovirus-like tubules were seen mainly in motor neurons; in the other, picorna-virus-like crystals were found in skeletal muscles. Different viruses can cause identical disease, but 2 different viruses in different sites in ALS also suggest that at least one type of particle is an adventitious finding of no general significance. An additional impetus to continue the search is the slowly progressive type C-virus myelitis in wild mice. This disease has many dissimilarities to ALS, including different morphology of the virus, but may provide a model for slow-virus amyotrophy.
临床医生已经注意到，以主要累及下运动神经元为主的肌萎缩侧索硬化症（ALS）与一种慢性脊髓灰质炎之间存在相似之处。偶尔有ALS病例在神经病理学上显示淋巴细胞浸润。苏联研究人员注意到了细胞质包涵体以及ALS可能传播给猴子的情况。关于后者的主要问题仍然存在，但在苏联以外的病例中也发现了包涵体，并且一直在寻找病毒。到目前为止，包括共培养技术在内的培养努力，在3个不同实验室中，使用死亡后2小时内进行尸检的ALS材料均未成功。在曾成功传播库鲁病、雅各布病和亚急性硬化性全脑炎的实验室中，这种材料以及其他病例的标本也未在动物身上引发可传播疾病。血清抗体研究也呈阴性。这些培养、传播和抗体研究的阴性结果并不能排除病毒病因：例如，在库鲁病中，多年后才证明其具有传染性，而这仍然是库鲁病具有传染性的唯一证据。从肾活检中获得了ALS存在免疫紊乱的证据，免疫抑制未带来任何临床益处，这可能表明肾脏检查结果揭示了对感染的反应，尽管是否为病毒感染甚至是否相关尚不清楚。将举例说明最近的2例ALS病例，其中通过电子显微镜在死后发现了病毒样颗粒。在1例中，主要在运动神经元中发现了黏液病毒样小管；在另1例中，在骨骼肌中发现了微小核糖核酸病毒样晶体。不同的病毒可导致相同的疾病，但在ALS的不同部位发现2种不同的病毒也表明，至少一种类型的颗粒是偶然发现，并无普遍意义。继续寻找的另一个推动力是野生小鼠中缓慢进展的C型病毒脊髓炎。这种疾病与ALS有许多不同之处，包括病毒形态不同，但可能为慢病毒肌萎缩提供一个模型。
