|Budget Amount *help
¥2,000,000 (Direct Cost : ¥2,000,000)
Fiscal Year 1994 : ¥1,000,000 (Direct Cost : ¥1,000,000)
Fiscal Year 1993 : ¥1,000,000 (Direct Cost : ¥1,000,000)
Ubiquitin-positive filamentous inclusions have been considered to represent abnormalities specific to amyotrophic lateral sclerosis (ALS). However, the inclusions have not yet been fully investigated in other neurological diseases and non-neurological controls. To evaluate the specificity of the filamentous inclusions, we studied, both immunohistochemically and immunoelectron microscopically, the motor neurons of the lumbosacral cords from 23 patients with ALS,31 patients with 19 different kinds of other neurological diseases (non-ALS) and 37 controls. We stained paraffin-embedded sections of the spinal cords by the avidin-biotin complex method using polyclonal anti-ubiquitin anti-bodies, and examined the anterior horn motor neurons. In ALS,we found 3 kinds of inclusions, i.e.filamentous and granular inclusions, and dense round bodies corresponding to Lewy bodies. Filamentous inclusions were observed in 19 of 23 patients with ALS,and in 1 of 31 non-ALS patients, but were not found in any of the 37 controls. Filamentous inclusions were more frequently observed in ALS patients than in non-ALS patients or controls (p<0.01). The non-ALS patient with filamentous inclusions had a B cell lymphoma which infiltrated the proximal parts of the peripheral nerves, causing marked central chromatolysis in the anterior horn motor neurons. On immunoelectron microscopy, the granular inclusions in ALS contained not only the constituents similar to those of the filamentous inclusions in ALS,but also lipofuscin granules, whereas the filamentous inclusions in the lymphoma patient showed the involvement of ribosomes. Although our data regarding the frequency of the filamentous inclusions further indicate the specificity of the inclusions in ALS,similar, if not identical, inclusions may also be observed in non-ALS patients. This suggests that ubiquitin-positive filamentous inclusions are characteristic of, but not pathognomonic of ALS.