Department of Chemistry, University of California-Davis, One Shields Avenue, Davis, California 95616, USA.
Anal Chem. 2012 Jan 3;84(1):396-402. doi: 10.1021/ac202775t. Epub 2011 Dec 19.
Serum N-glycan profiles for use as clinical biomarkers of disease(s) is of increasing scientific interest. Promising profiles have already been identified in several diseases, including cancer, Alzheimer's, and diabetes. Venipuncture is routinely performed to collect the blood necessary for this type of analysis, but blood from a fingerstick placed on filter paper (known as dried blood spots (DBS)) is more advantageous. This sampling method is less invasive than "classical" blood drawing, can be performed conveniently at home, and avoids cumbersome shipping and storage procedures. Here, we present a procedure for N-glycan profiling of DBS samples consisting of reconstitution of DBS in N-glycan release buffer, protein denaturation, enzymatic N-glycan release and PGC Solid phase extraction (SPE) for purification. Samples are then analyzed using nanoHPLC-PGC-chip-TOF-MS to generate N-glycan profiles. Using this method, ~150 N-glycan structures can be monitored, originating from 44 N-glycan compositions that can be analyzed with good repeatability (the coefficient of variation (%CV) is ~20%). To assess the stability of the N-glycans during storage, DBS samples were stored at room temperature (RT) and -80 °C. No major differences in N-glycan composition could be observed. Moreover, upon comparison of the N-glycan profile of DBS with profiles obtained from serum, which is a classical matrix for N-glycan profiling, similar patterns were observed. The method facilitates large population studies for N-glycan profiling, and is especially advantageous for children and the elderly, who have limited blood supplies, as well as animal studies in small mammals.
血清 N-糖谱分析作为疾病的临床生物标志物正引起越来越多的科学关注。在包括癌症、阿尔茨海默病和糖尿病在内的几种疾病中,已经确定了有前景的 N-糖谱。为了进行这种类型的分析,通常需要采集静脉血,但从置于滤纸上的指尖采血(称为干血斑 (DBS))则更具优势。这种采样方法比“经典”采血更具侵入性,可以方便地在家中进行,并且避免了繁琐的运输和储存程序。在这里,我们提出了一种 DBS 样本 N-糖谱分析的程序,包括 DBS 在 N-糖释放缓冲液中的重组成分、蛋白质变性、酶促 N-糖释放和 PGC 固相萃取 (SPE) 用于纯化。然后使用 nanoHPLC-PGC-chip-TOF-MS 分析样品,生成 N-糖谱。使用这种方法,可以监测约 150 种 N-糖结构,这些结构源自 44 种 N-糖组成,可以进行很好的重复性分析(变异系数 (%CV) 约为 20%)。为了评估 N-糖在储存过程中的稳定性,将 DBS 样本储存在室温 (RT) 和 -80°C。在 N-糖组成方面没有观察到明显差异。此外,与作为 N-糖谱分析经典基质的血清相比,DBS 的 N-糖谱模式也非常相似。该方法有利于进行 N-糖谱的大规模人群研究,对于血供有限的儿童和老年人,以及小型哺乳动物的动物研究,尤其具有优势。