C5b-9在坏死性肌病肌肉组织血管中的表达及意义

Role of C5b-9 expression in skeletal muscle blood vessels in necrotizing myopathy

目的研究C5b-9在坏死性肌病肌肉小血管中的表达以探讨其发病机制。方法采用酶组织化学和免疫组织化学方法检测坏死性肌病患者肌肉组织肌纤维和血管的MHC-1和C5b-9表达。结果本组患者肌肉组织出现灶性或散在分布的肌纤维坏死,间有吞噬现象,肌内、外衣和血管周围未见炎性细胞浸润,局部小血管数量减少,个别小血管管壁增厚。MHC-I免疫组化染色显示坏死的肌纤维、肌纤维间隙及血管均呈阴性。C5b-9免疫组化染色显示肌肉组织的小动脉与小静脉的血管壁,内皮细胞及平滑肌均出现明显的强阳性表达,同时相关的坏变和萎缩肌纤维也出现明显的表达。结论 C5b-9可能参与血管启动的坏死性肌病的发病机制。

Objective To investigate the expression of C5b-9 in the skeletal muscle blood vessels in patients with necrotizing myopathy and explore its role in the pathogenesis of this disease.Methods The expression of C5b-9 and MHC-I in the skeletal muscular fibers and blood vessels in 4 patients with necrotizing myopathy was detected using enzymohistochemistry and immunohistochemistry.Results Focal or dispersive necrotic muscle fibers with obvious phagocytosis were observed in all the 4 patients.No inflammatory cell infiltration was found in the perimysium or perivascular regions.HE staining showed a decreased number of local small blood vessels,and the some small blood vessels showed thickened vascular walls.Immunohistochemistry detected prominent C5b-9 expression in the necrotic muscle fibers and the blood vessels,and diffuse strong C5b-9 expression was found in the vascular walls,vascular endothelial cells and the smooth muscle layer.No MHC-I deposition was detected in the muscular fibers and blood vessels.Conclusion C5b-9 contributes to the pathogenesis of necrotizing myopathy mediated by pathologies in the blood vessels.