Department of Chemistry, University Wyoming, Laramie, WY 82071, USA.
Anal Biochem. 2011 Jan 15;408(2):289-96. doi: 10.1016/j.ab.2010.09.017. Epub 2010 Sep 22.
A method is described using desorption electrospray ionization (DESI) mass spectrometry (MS) to obtain phospholipid mass spectral profiles from crude lung tissue extracts. The measured DESI mass spectral lipid fingerprints were then analyzed by unsupervised learning principal components analysis (PCA). This combined approach was used to differentiate the effect(s) of two vaccination routes on lipid composition in mouse lungs. Specifically, the two vaccination routes compared were intranasal (i.n.) and intradermal (i.d.) inoculation of the Francisella tularensis live vaccine strain (Ft-LVS). Lung samples of control and LVS-inoculated mice were quickly extracted with a methanol/chloroform solution, and the crude extract was directly analyzed by DESI-MS, with a total turnaround time of less than 10 min/sample. All of the measured DESI mass spectra (in both positive and negative ion mode) were compared via PCA, resulting in clear differentiation of mass spectral profiles of i.n.-inoculated mouse lung tissues from those of i.d.-inoculated and control mouse lung tissues. Lipid biomarkers responsible for sample differentiation were identified via tandem MS (MS/MS) measurements or by comparison with mass spectra of lipid standards. The DESI-MS approach described here provided a practical and rapid means to analyze tissue samples without extensive extractions and solvent changes.
本文描述了一种使用解吸电喷雾电离（DESI）质谱（MS）从粗肺组织提取物中获得磷脂质质谱谱图的方法。然后通过无监督学习主成分分析（PCA）对所测量的 DESI 质谱脂质指纹图谱进行分析。这种组合方法用于区分两种疫苗接种途径对小鼠肺部脂质组成的影响。具体来说，比较了两种疫苗接种途径：鼻内（i.n.）和皮内（i.d.）接种弗氏志贺氏杆菌活疫苗株（Ft-LVS）。用甲醇/氯仿溶液快速提取对照和 LVS 接种小鼠的肺样品，并用 DESI-MS 直接分析粗提取物，每个样品的总周转时间不到 10 分钟。通过 PCA 比较所有测量的 DESI 质谱（正离子和负离子模式），导致鼻内接种小鼠肺组织的质谱谱图与皮内接种和对照小鼠肺组织的质谱谱图明显区分。通过串联 MS（MS/MS）测量或与脂质标准品的质谱比较，确定了导致样品分化的脂质生物标志物。本文描述的 DESI-MS 方法提供了一种实用且快速的方法，无需进行广泛的提取和溶剂更换即可分析组织样品。
