Department of Genetics, Semmelweis University, Budapest, Hungary.
Immunol Lett. 2010 Feb 16;128(2):124-30. doi: 10.1016/j.imlet.2009.12.018. Epub 2010 Jan 4.
Microparticles are recently recognized players of intercellular communication. They are involved in signal transduction, cell activation and apoptosis. Their importance is also suggested in autoimmune diseases such as rheumatoid arthritis and systemic sclerosis. We investigated the role of microparticles in polymyositis/dermatomyositis, a group of rare autoimmune diseases, characterized by specific skin lesions and muscle weakness. The plasma concentration of monocyte and lymphocyte derived microparticles of 20 patients with polymyositis/dermatomyositis and 20 healthy controls were determined by flow cytometry. The structure of microparticles was visualized by electron microscopy. Significantly elevated numbers of monocyte (CD14 positive), T-lymphocyte (CD3 positive) and B-lymphocyte (CD19 positive) derived microparticles were found in the plasma samples of polymyositis/dermatomyositis patients, compared to healthy controls (p=0.001, 0.01 and 0.006, respectively). Furthermore, the plasma levels of monocyte and B-lymphocyte derived microparticles correlated with the manual muscle strength test (r=0.497, p=0.027; r=0.508, p=0.023; respectively). Patients with anti-Jo-1 antibody and lung involvement had significantly higher numbers of T- and B-lymphocyte and monocyte derived MPs (p=0.006, 0.012 and 0.007, respectively, for anti-Jo-1; p=0.013, 0.016 and 0.025, respectively, for lung involvement). After ultracentrifugation, CK activity could be detected only in traces in the resuspended pellet containing microparticles of healthy and diseased individuals. The electron microscopy revealed slightly different microparticles in the samples of patients with polymyositis/dermatomyositis. These results suggest that immune cell derived microparticles may contribute to the inflammatory process in polymyositis/dermatomyositis, however, CK-positive, possibly muscle derived microparticles do not seem to be present in the blood of patients with polymyositis/dermatomyositis.
微粒体是最近被发现的细胞间通讯的参与者。它们参与信号转导、细胞激活和细胞凋亡。它们在类风湿关节炎和系统性硬化症等自身免疫性疾病中的重要性也得到了提示。我们研究了微粒体在多发性肌炎/皮肌炎中的作用，多发性肌炎/皮肌炎是一组罕见的自身免疫性疾病，其特征是特定的皮肤损伤和肌肉无力。通过流式细胞术测定了 20 例多发性肌炎/皮肌炎患者和 20 例健康对照者的单核细胞和淋巴细胞衍生微粒体的血浆浓度。通过电子显微镜观察微粒体的结构。与健康对照组相比，多发性肌炎/皮肌炎患者的血浆样本中发现单核细胞（CD14 阳性）、T 淋巴细胞（CD3 阳性）和 B 淋巴细胞（CD19 阳性）衍生的微粒体数量显著升高（分别为 p=0.001、0.01 和 0.006）。此外，单核细胞和 B 淋巴细胞衍生微粒体的血浆水平与手动肌肉力量测试相关（r=0.497，p=0.027；r=0.508，p=0.023）。抗 Jo-1 抗体和肺部受累的患者 T 淋巴细胞和 B 淋巴细胞和单核细胞衍生的 MPs 数量明显更高（分别为 p=0.006、0.012 和 0.007，抗 Jo-1；p=0.013、0.016 和 0.025，分别为肺部受累）。超速离心后，仅在健康和患病个体的微粒体重悬沉淀中检测到 CK 活性的痕迹。电子显微镜显示多发性肌炎/皮肌炎患者样本中的微粒体略有不同。这些结果表明，免疫细胞衍生的微粒体可能有助于多发性肌炎/皮肌炎的炎症过程，但 CK 阳性、可能来源于肌肉的微粒体似乎不存在于多发性肌炎/皮肌炎患者的血液中。
