Bilak M, Askanas V, Engel W K
Department of Neurology, University of Southern California School of Medicine, Los Angeles 90017.
Acta Neuropathol. 1993;85(4):378-82. doi: 10.1007/BF00334447.
In 10 of 10 inclusion-body myositis (IBM) patients, including 1 hereditary case, vacuolated muscle fibers contained large or small cytoplasmic inclusions immunoreactive for alpha 1-antichymotrypsin (alpha 1-ACT). All IBM muscle biopsies had characteristic cytoplasmic tubulo-filaments by electron microscopy. None of 17 control muscle biopsies contained the alpha 1-ACT immunoreactive inclusions characteristic of IBM. In vacuolated muscle fibers, alpha 1-ACT immunoreactive inclusions colocalized with beta-amyloid protein and ubiquitin immunoreactivities. Our study provides the first demonstration of alpha 1-ACT accumulations in abnormal human muscle, and it suggest that, as in Alzheimer's disease and Down's syndrome, alpha 1-ACT may be involved in the pathogenesis of IBM.
在10例包涵体肌炎（IBM）患者中（包括1例遗传病例），空泡化肌纤维含有对α1抗糜蛋白酶（α1-ACT）呈免疫反应性的大小不等的胞质包涵体。所有IBM肌肉活检标本通过电子显微镜检查均有特征性的胞质微管丝。17例对照肌肉活检标本中均未发现具有IBM特征的α1-ACT免疫反应性包涵体。在空泡化肌纤维中，α1-ACT免疫反应性包涵体与β淀粉样蛋白和泛素免疫反应性共定位。我们的研究首次证实了α1-ACT在异常人类肌肉中的积聚，并且提示，如同在阿尔茨海默病和唐氏综合征中一样，α1-ACT可能参与了IBM的发病机制。
