Children's Hospital Informatics Program, Division of Neuromuscular Disease, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.
Ann Neurol. 2010 Jan;67(1):53-63. doi: 10.1002/ana.21805.
We investigated interferon-stimulated gene 15 (ISG15), a poorly understood ubiquitin-like modifier, and its enzymatic pathway in dermatomyositis (DM), an autoimmune disease primarily involving muscle and skin.
We generated microarray data measuring transcript abundance for approximately 18,000 genes in each of 113 human muscle biopsy specimens, and studied biopsy specimens and cultured skeletal muscle using immunohistochemistry, immunoblotting proteomics, real-time quantitative polymerase chain reaction, and laser-capture microdissection.
Transcripts encoding ISG15-conjugation pathway proteins were markedly upregulated in DM with perifascicular atrophy (DM-PFA) muscle (ISG15 339-fold, HERC5 62-fold, and USP18 68-fold) compared with 99 non-DM samples. Combined analysis with publicly available microarray datasets showed that >50-fold ISG15 transcript elevation had 100% sensitivity and specificity for 28 biopsies from adult DM-PFA and juvenile DM patients compared with 199 muscle samples from other muscle diseases. Free ISG15 and ISG15-conjugated proteins were only found on immunoblots from DM-PFA muscle. Cultured human skeletal muscle exposed to type 1 interferons produced similar transcripts and ISG15 protein and conjugates. Laser-capture microdissection followed by proteomic analysis showed deficiency of titin in DM perifascicular atrophic myofibers.
A large-scale microarray study of muscle samples demonstrated that among a diverse group of muscle diseases DM was uniquely associated with upregulation of the ISG15 conjugation pathway. Exposure of human skeletal muscle cell culture to type 1 interferons produced a molecular picture highly similar to that seen in human DM muscle. Perifascicular atrophic myofibers in DM were deficient in a number of skeletal muscle proteins including titin.
我们研究了干扰素刺激基因 15（ISG15），一种了解甚少的泛素样修饰物，及其在皮肌炎（DM）中的酶促途径，DM 是一种主要累及肌肉和皮肤的自身免疫性疾病。
我们生成了微阵列数据，测量了 113 个人类肌肉活检样本中约 18000 个基因的转录丰度，并使用免疫组织化学、免疫印迹蛋白质组学、实时定量聚合酶链反应和激光捕获显微切割研究了活检样本和培养的骨骼肌。
与 99 个非 DM 样本相比，具有围带萎缩（DM-PFA）的 DM 肌肉中的 ISG15 结合途径蛋白的转录物明显上调（ISG15 上调 339 倍，HERC5 上调 62 倍，USP18 上调 68 倍）。与来自其他肌肉疾病的 199 个肌肉样本相比，与来自成人 DM-PFA 和青少年 DM 患者的 28 个活检样本的结合分析显示，>50 倍的 ISG15 转录物升高对成人 DM-PFA 和青少年 DM 患者的肌肉疾病具有 100%的敏感性和特异性。仅在 DM-PFA 肌肉的免疫印迹中发现游离 ISG15 和 ISG15 结合蛋白。暴露于 1 型干扰素的培养人骨骼肌产生了相似的转录物和 ISG15 蛋白和缀合物。激光捕获显微切割后进行蛋白质组学分析显示，DM 围带萎缩肌纤维中的肌联蛋白缺失。
对肌肉样本进行的大规模微阵列研究表明，在一组不同的肌肉疾病中，DM 是唯一与 ISG15 结合途径上调相关的疾病。将人骨骼肌细胞培养物暴露于 1 型干扰素可产生与人 DM 肌肉非常相似的分子图像。DM 中的围带萎缩肌纤维缺乏许多骨骼肌蛋白，包括肌联蛋白。
