Analytical Biochemistry, Department of Pharmacy, University of Groningen, Groningen, the Netherlands.
Clin Chem. 2011 Dec;57(12):1703-11. doi: 10.1373/clinchem.2011.167601. Epub 2011 Oct 13.
Because cerebrospinal fluid (CSF) is in close contact with diseased areas in neurological disorders, it is an important source of material in the search for molecular biomarkers. However, sample handling for CSF collected from patients in a clinical setting might not always be adequate for use in proteomics and metabolomics studies.
We left CSF for 0, 30, and 120 min at room temperature immediately after sample collection and centrifugation/removal of cells. At 2 laboratories CSF proteomes were subjected to tryptic digestion and analyzed by use of nano-liquid chromatography (LC) Orbitrap mass spectrometry (MS) and chipLC quadrupole TOF-MS. Metabolome analysis was performed at 3 laboratories by NMR, GC-MS, and LC-MS. Targeted analyses of cystatin C and albumin were performed by LC-tandem MS in the selected reaction monitoring mode.
We did not find significant changes in the measured proteome and metabolome of CSF stored at room temperature after centrifugation, except for 2 peptides and 1 metabolite, 2,3,4-trihydroxybutanoic (threonic) acid, of 5780 identified peptides and 93 identified metabolites. A sensitive protein stability marker, cystatin C, was not affected.
The measured proteome and metabolome of centrifuged human CSF is stable at room temperature for up to 2 hours. We cannot exclude, however, that changes undetectable with our current methodology, such as denaturation or proteolysis, might occur because of sample handling conditions. The stability we observed gives laboratory personnel at the collection site sufficient time to aliquot samples before freezing and storage at -80 °C.
由于脑脊液（CSF）与神经系统疾病的病变部位密切接触，因此它是寻找分子生物标志物的重要物质来源。然而，从临床环境中采集的 CSF 样本的处理方式在用于蛋白质组学和代谢组学研究时可能并不总是足够的。
我们在采集和离心/去除细胞后立即将 CSF 在室温下放置 0、30 和 120 分钟。在 2 个实验室中，CSF 蛋白质组通过使用纳升液相色谱（LC）Orbitrap 质谱（MS）和芯片 LC 四极杆 TOF-MS 进行胰蛋白酶消化和分析。代谢组分析在 3 个实验室中通过 NMR、GC-MS 和 LC-MS 进行。在选定的反应监测模式下通过 LC-串联 MS 对胱抑素 C 和白蛋白进行靶向分析。
我们没有发现离心后室温下储存的 CSF 测量的蛋白质组和代谢组发生明显变化，除了 2 个肽和 1 个代谢物 2,3,4-三羟基丁酸（苏糖酸），在 5780 个鉴定的肽和 93 个鉴定的代谢物中。作为一种敏感的蛋白质稳定性标志物，胱抑素 C 不受影响。
离心后的人 CSF 测量的蛋白质组和代谢组在室温下稳定长达 2 小时。然而，我们不能排除由于样本处理条件，可能会发生我们当前方法无法检测到的变化，例如变性或蛋白水解。我们观察到的稳定性为采集现场的实验室人员提供了足够的时间，在将样品冷冻并储存在-80°C 之前进行等分。
