Abstract：
Phospholipids are vital constituents of the cell membrane and aid in signal transduction. Phospholipid profiles vary distinctively with the cell type. Notably, specific phospholipid molecules are present in significantly higher or lower concentrations in cancer cells versus normal cells. In this study, live single-cell mass spectrometry (MS) was developed for analyzing phospholipids at the single-cell level. This method facilitates rapid molecular analysis of cells under microscopic observation. For nanoelectrospray ionization, phospholipids were extracted from single cells isolated in a glass capillary through a high-efficiency process. Cell-derived phosphatidylcholines were detected with high sensitivity when trehalose C14 was added as a solubilizing reagent. Trehalose C14 can solubilize cells at low concentrations owing to its low critical micelle concentration, and exerts minimal matrix effects (such as suppressing ionization and causing peak overlap) in the MS analysis of cellular molecules. Analyses of phospholipids in Raji and HEV0070 cells using the developed method revealed specific peaks of phosphatidylcholine and sphingomyelin in the respective cells. The developed technique not only affords phospholipid profiles at the single-cell level, but also holds promise for identifying biomarkers associated with various diseases, particularly cancer.
摘要：
磷脂是细胞膜的重要成分，有助于信号转导。磷脂谱随细胞类型的不同而不同。值得注意的是,与正常细胞相比，特定的磷脂分子在癌细胞中以明显更高或更低的浓度存在。在这项研究中,开发了活单细胞质谱(MS)用于在单细胞水平上分析磷脂。该方法有助于在显微镜观察下对细胞进行快速分子分析。对于纳米电喷雾电离，通过高效过程从玻璃毛细管中分离的单细胞中提取磷脂。当添加海藻糖C14作为增溶剂时，可以高灵敏度地检测到细胞来源的磷脂酰胆碱。海藻糖C14由于其低的临界胶束浓度，可以在低浓度下溶解细胞。并且在细胞分子的MS分析中施加最小的基体效应(例如抑制电离和引起峰重叠)。使用开发的方法分析Raji和HEV0070细胞中的磷脂，揭示了各自细胞中磷脂酰胆碱和鞘磷脂的特定峰。所开发的技术不仅在单细胞水平提供磷脂谱，但也有望识别与各种疾病相关的生物标志物，尤其是癌症。
