Intact Protein Analysis of Ubiquitin in Cerebrospinal Fluid by Multiple Reaction Monitoring Reveals Differences in Alzheimer's Disease and Frontotemporal Lobar Degeneration
Intact Protein Analysis of Ubiquitin in Cerebrospinal Fluid by Multiple Reaction Monitoring Reveals Differences in Alzheimer's Disease and Frontotemporal Lobar Degeneration
复制标题
DOI：
10.1021/pr5006058
复制
发表时间：
2014-11-01
影响因子：
4.4
通讯作者：
Otto, Markus
中科院分区：
文献类型：
--
作者：
Oeckl, Patrick;Steinacker, Petra;Otto, Markus
泛素-蛋白酶体系统（UPS）的损伤被认为是神经退行性疾病的早期事件，监测UPS的变化可能作为疾病的生物标志物。我们的目标是建立一种基于抗体的检测方法的替代方法，用于选择性测量脑脊液（CSF）中的游离单核白蛋白。采用液相色谱-多反应监测质谱法（LC-MS/MS）测定阿尔茨海默病（AD）、肌萎缩侧索硬化症（ALS）、额颞叶痴呆行为变异型（bvFTD）、克雅氏病（CJD）、帕金森病（PD）、原发性进行性失语症（PPA）和进行性核上性麻痹（PSP）患者CSF中的游离单核白蛋白。LC-MS/MS方法显示出良好的批内和批间精密度（4.4-7.4%和4.9-10.3%）和准确度（100-107%和100-106%）。与对照组（33.0 +/- 9.7 ng/mL）相比，AD（47.5 +/- 13.1 ng/mL，p < 0.05）和CJD患者（171.5 +/- 103.5 ng/mL，p < 0.001）的CSF泛素浓度增加，但在其他神经退行性疾病中没有。接受者工作特征曲线（ROC）分析显示，AD与对照组患者的曲线下面积（AUC）为0.832，特异性和敏感性分别为75%和75%。AD和FTLD患者的ROC分析得到的AUC为0.776，特异性和敏感性分别为53%和100%。总之，我们的LC-MS/MS方法可能有助于更广泛的社区泛素测定，并可能有助于区分AD，CJD和FTLD患者。
The impairment of the ubiquitin-proteasome system (UPS) is thought to be an early event in neurodegeneration, and monitoring UPS alterations might serve as a disease biomarker. Our aim was to establish an alternate method to antibody-based assays for the selective measurement of free monoubiquitin in cerebrospinal fluid (CSF). Free monoubiquitin was measured with liquid chromatography-multiple reaction monitoring mass spectrometry (LC-MS/MS) in CSF of patients with Alzheimer's disease (AD), amyotrophic lateral sclerosis (ALS), behavioral variant of frontotemporal dementia (bvFTD), Creutzfeldt-Jakob disease (CJD), Parkinson's disease (PD), primary progressive aphasia (PPA), and progressive supranuclear palsy (PSP). The LC-MS/MS method showed excellent intra- and interassay precision (4.4-7.4% and 4.9-10.3%) and accuracy (100-107% and 100-106%). CSF ubiquitin concentration was increased compared with that of controls (33.0 +/- 9.7 ng/mL) in AD (47.5 +/- 13.1 ng/mL, p < 0.05) and CJD patients (171.5 +/- 103.5 ng/mL, p < 0.001) but not in other neurodegenerative diseases. Receiver operating characteristic curve (ROC) analysis of AD vs control patients revealed an area under the curve (AUC) of 0.832, and the specificity and sensitivity were 75 and 75%, respectively. ROC analysis of AD and FTLD patients yielded an AUC of 0.776, and the specificity and sensitivity were 53 and 100%, respectively. In conclusion, our LC-MS/MS method may facilitate ubiquitin determination to a broader community and might help to discriminate AD, CJD, and FTLD patients.