You Jin-Sam, Gelfanova Valentina, Knierman Michael D, Witzmann Frank A, Wang Mu, Hale John E
Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN, USA.
Proteomics. 2005 Jan;5(1):290-6. doi: 10.1002/pmic.200400889.
Human cerebrospinal fluid (CSF) is in direct contact with the brain extracellular space. Beside the secretion of CSF by the choroid plexus the fluid also derives directly from the brain by the ependymal lining of the ventricular system and the glial membrane and from blood vessels in the arachnoid. Therefore, biochemical change in the brain may be reflected in the CSF. CSF is a potential source of protein molecular indices of central nervous system function and pathology. However, various amounts of blood contamination in CSF may arise during sample acquisition. The concentration of protein in the CSF is only 0.2 to 0.5% that of blood. Minor contamination of CSF with blood during collection of the fluid may dramatically alter the protein profile confounding the identification of potential biomarkers. We have analyzed CSF and CSF spiked with increasing amounts of whole blood using proteomic techniques. We detected at least four blood specific highly abundant proteins: hemoglobin, catalase, peroxiredoxin and carbonic anhydrase I. These proteins can be used as blood contamination markers for proteomic analysis of CSF. Proteins in blood contaminated CSF samples were less stable compared to neat CSF at 37 degrees C suggesting that blood borne protease may induce protein degradation in CSF during sample acquisition. This analysis was aimed at identification of proteins found primarily in CSF, those found primarily in blood and assessment of the impact of blood contamination on those proteins found in both fluids.
人类脑脊液（CSF）与脑细胞外间隙直接接触。除了脉络丛分泌脑脊液外，脑脊液还直接来源于脑室系统的室管膜内衬、神经胶质膜以及蛛网膜中的血管。因此，大脑中的生化变化可能会反映在脑脊液中。脑脊液是中枢神经系统功能和病理状态下蛋白质分子指标的潜在来源。然而，在样本采集过程中，脑脊液可能会受到不同程度的血液污染。脑脊液中的蛋白质浓度仅为血液的0.2%至0.5%。在采集脑脊液时，若脑脊液受到少量血液污染，可能会显著改变蛋白质谱，从而混淆潜在生物标志物的识别。我们使用蛋白质组学技术分析了脑脊液以及添加了不同量全血的脑脊液。我们检测到至少四种血液特异性高丰度蛋白：血红蛋白、过氧化氢酶、过氧化物酶和碳酸酐酶I。这些蛋白质可作为脑脊液蛋白质组学分析中的血液污染标志物。与37℃下的纯脑脊液相比，受血液污染的脑脊液样本中的蛋白质稳定性较差，这表明血液中的蛋白酶可能在样本采集过程中诱导脑脊液中的蛋白质降解。该分析旨在鉴定主要存在于脑脊液中的蛋白质、主要存在于血液中的蛋白质，并评估血液污染对两种液体中都存在的蛋白质的影响。
