Department of Environmental and Occupational Health, National Cheng Kung University, Tainan, Taiwan.
Proteomics Clin Appl. 2007 May;1(5):506-12. doi: 10.1002/prca.200600684. Epub 2007 Apr 19.
The objective of this study was to search for biological markers associated with Alzheimer's disease (AD). Plasma specimens obtained from ten pathologically diagnosed AD patients and ten non-demented (ND) control subjects were analyzed by a combination of 2-DE and MS. This strategy allowed us to identify six plasma proteins (alpha-1-antitrypsin, vitamin D-binding protein, inter-alpha-trypsin inhibitor family heavy chain-related protein, apolipoprotein J precursor, cAMP-dependent protein kinase catalytic subunit alpha 1, and an orf) whose 2-DE spot densities were different between the AD and ND groups. Due to their involvements in AD amyloid plaque formation, the plasma concentrations of alpha-1-antitrypsin and apolipoprotein J were further validated using either ELISA or Western blot. The results revealed that the plasma levels of alpha-1-antitrypsin in AD were higher than those of controls, confirming the 2-DE findings. However, no difference in total apolipoprotein J concentration was observed between the AD and ND groups. Considering the difference in resolving power to differentially quantitate protein isoforms provided by 2-DE and Western blot, 2-DE analysis combined with MS protein identification offers distinctive advantages when a disease-related protein isoform-specific variance is investigated.
本研究旨在寻找与阿尔茨海默病（AD）相关的生物标志物。通过二维电泳（2-DE）和质谱（MS）联用分析了 10 例经病理诊断的 AD 患者和 10 例非痴呆（ND）对照者的血浆标本。该策略使我们能够鉴定出 6 种血浆蛋白（α-1-抗胰蛋白酶、维生素 D 结合蛋白、α-胰蛋白酶抑制剂重链相关蛋白家族、载脂蛋白 J 前体、cAMP 依赖性蛋白激酶催化亚单位α1 和一个 ORF），其在 AD 和 ND 组之间的 2-DE 点密度不同。由于它们参与 AD 淀粉样斑块形成，因此使用 ELISA 或 Western blot 进一步验证了 α-1-抗胰蛋白酶和载脂蛋白 J 的血浆浓度。结果表明，AD 患者的血浆α-1-抗胰蛋白酶水平高于对照组，证实了 2-DE 的发现。然而，AD 和 ND 组之间总载脂蛋白 J 浓度没有差异。考虑到 2-DE 和 Western blot 在定量分析蛋白异构体方面的分辨率差异，当研究与疾病相关的蛋白异构体特异性差异时，2-DE 分析结合 MS 蛋白鉴定具有独特的优势。
