National Physical Laboratory, NiCE-MSI, Teddington, Middlesex, UK.
ION-TOF GmbH, Münster, Germany.
Nat Methods. 2017 Dec;14(12):1175-1183. doi: 10.1038/nmeth.4504. Epub 2017 Nov 13.
We report the development of a 3D OrbiSIMS instrument for label-free biomedical imaging. It combines the high spatial resolution of secondary ion mass spectrometry (SIMS; under 200 nm for inorganic species and under 2 μm for biomolecules) with the high mass-resolving power of an Orbitrap (>240,000 at m/z 200). This allows exogenous and endogenous metabolites to be visualized in 3D with subcellular resolution. We imaged the distribution of neurotransmitters-gamma-aminobutyric acid, dopamine and serotonin-with high spectroscopic confidence in the mouse hippocampus. We also putatively annotated and mapped the subcellular localization of 29 sulfoglycosphingolipids and 45 glycerophospholipids, and we confirmed lipid identities with tandem mass spectrometry. We demonstrated single-cell metabolomic profiling using rat alveolar macrophage cells incubated with different concentrations of the drug amiodarone, and we observed that the upregulation of phospholipid species and cholesterol is correlated with the accumulation of amiodarone.
我们报告了一种用于无标记生物医学成像的 3D OrbiSIMS 仪器的开发。它将二次离子质谱（SIMS；无机物质的空间分辨率低于 200nm，生物分子的空间分辨率低于 2μm）与轨道阱（m/z 200 时大于 240,000）的高质量分辨率相结合。这使得外源性和内源性代谢物能够以亚细胞分辨率在 3D 中可视化。我们在小鼠海马体中以高光谱置信度成像了神经递质 - γ-氨基丁酸、多巴胺和血清素的分布。我们还推测注释并绘制了 29 种硫糖脂和 45 种甘油磷脂的亚细胞定位，并通过串联质谱法确认了脂质的身份。我们使用用不同浓度的药物胺碘酮孵育的大鼠肺泡巨噬细胞进行了单细胞代谢组学分析，并观察到磷脂种类和胆固醇的上调与胺碘酮的积累相关。
