Dalakas M C, Sivakumar K
Neuromuscular Diseases Section, National Institute of Neurological Disorders and Stroke, National Institute of Health, Bethesda, Maryland 20892, USA.
Curr Opin Neurol. 1996 Jun;9(3):235-9. doi: 10.1097/00019052-199606000-00015.
In polymyositis and sporadic inclusion body myositis, clonal expansion of CD8+ cells which are primed to recognize previously unknown muscle antigens occurs. Compared with sporadic inclusion body myositis, however, in which the T-cell response may not be antigen driven, there is in polymyositis an overexpression of certain T-cell receptor gene families among the autoinvasive T-cells. Although studies on the endomysial expression of cytokines and cell adhesion molecules have provided additional support for the concept of an ongoing immune process, the site of sensitization and the mechanism by which the autoimmune process is triggered remains to be established. In dermatomyositis, a multiorgan disease, evidence exists that the complement-mediated microvascular injury by the putative antibody may not be limited to the endomysial vessels but may also involve the blood vessels in the dermis. The antigenic target on the endothelial cell in dermatomyositis patients and the pathogenic role of the recently studied anti-Mi-2 antibody directed against a helicase are still to be determined.
在多发性肌炎和散发性包涵体肌炎中，会出现经致敏以识别先前未知肌肉抗原的CD8+细胞的克隆性扩增。然而，与散发性包涵体肌炎（其中T细胞反应可能并非由抗原驱动）相比，在多发性肌炎中，自身侵袭性T细胞中某些T细胞受体基因家族存在过表达。尽管关于肌内膜细胞因子和细胞黏附分子表达的研究为正在进行的免疫过程这一概念提供了更多支持，但致敏部位以及自身免疫过程触发机制仍有待确定。在皮肌炎（一种多器官疾病）中，有证据表明，假定抗体介导的补体微血管损伤可能不仅限于肌内膜血管，还可能累及真皮中的血管。皮肌炎患者内皮细胞上的抗原靶点以及最近研究的针对解旋酶的抗Mi-2抗体的致病作用仍有待确定。
