B7-H1分子免疫病理在多发性肌炎中的临床研究

目的 通过免疫组化染色了解协同刺激分子B7-H1蛋白在多发性肌炎(PM)和肢带型肌营养不良2B型(LGMD 28)患者肌组织中的表达情况,探讨其在PM诊断和鉴别诊断中的意义.方法 选择苏州大学附属第一医院神经内科自2006年1月至2009年12月收治的43例PM患者(PM组),26例LGMD 2B型患者(LGMD 2B组)及21例肌活检正常者(对照组).对所有成员行肌肉活检,冰冻切片后进行常规HE染色、免疫组织化学染色,检测肌组织中B7-H1蛋白的表达.结果 (1)PM组与LGMD 2B型组肌肉活检普通病理染色结果相似,表现为不同程度的坏死、吞噬、再生现象,伴有不同程度的炎细胞浸润.(2)PM组B7-H1蛋白阳性表达主要定位于细胞膜,呈棕黄色至棕褐色,主要集中在有炎细胞浸润的变性、坏死肌纤维上;其肌组织中B7-H1蛋白表达水平比较LGMD2B型组和对照组成员肌组织中水平明显增高(分别为69.77%、26.92%、4.76%),差异有统计学意义(P<0.05).结论 协同刺激分子B7-H1在PM患者肌组织中高表达,参与了PM的免疫学发病机制,可成为PM与继发性炎细胞浸润性肌病相鉴别的免疫病理标志.

Immuno-pathogenesis of B7-H1 in polymyositis

Objective To analyze the protein expression of costimulatory molecule B7-H1 in muscular tissues of patients with polymyositis (PM) and limb-girdle muscular dystrophy-2B type (LGMD-2B), and investigate its relevance to the pathogenesis of PM and its role in the diagnosis and identification of PM. Methods Forty-three patients with PM, 26 patients with LGMD -2B and 21 with normal muscle biopsy were recruited. Muscle biopsy was performed before frozen sections, and then, HE staining and immunohistochemistry were employed to detect the protein expression of B7-H1 in muscle tissues of each group. Results The results of HE staining of muscle tissues in the PM group and LGMD 2B group were very similar; varying degrees of necrosis, phagocytosis and regeneration phenomenon were noted with varying degrees of inflammatory cell infiltration. In PM group,muscle-related expression of B7-H1 was observed on the surface of muscle fibers (the cytomembrane). It was localized in areas where inflammatory cells lay in close apposition to damaged or non-necrotic muscle fibers. The B7-H1 protein in the PM muscular tissue was significantly increased as compared with that in the LGMD -2B tissue and normal tissue (69.77%, 26.92%, 4.76%, P<0.05). Conclusion Costimulatory molecule B7-H1 is highly expressed in the muscular tissue of patients with PM and it may be involved in the immunological pathogenesis of PM. It can be used to make a distinction between PM and other myopathies that have secondary inflammatory changes.