University of Münster, Institute of Inorganic and Analytical Chemistry, Corrensstraße 30, 48149 Münster, Germany.
University of Münster, University Hospital Münster, Department of Anesthesiology, Intensive Care and Pain Medicine, Albert-Schweitzer-Campus 1, 48149 Münster, Germany.
J Trace Elem Med Biol. 2019 Mar;52:166-175. doi: 10.1016/j.jtemb.2018.12.012. Epub 2018 Dec 22.
Hereditary hemochromatosis is the most common autosomal recessive genetic disorder of the iron metabolism. Iron accumulation in various organs, especially in liver and pancreas leads to diseases and may cause organ failure. In this study, methods for elemental bioimaging by means of quantitative micro X-ray fluorescence analysis (μXRF) and laser ablation-inductively coupled plasma-triple quadrupole mass spectrometry (LA-ICP-TQMS) were developed and applied to investigate the pathophysiological development of iron accumulation in murine tissue based on animals with an iron-overload phenotype caused by a hepatocyte-specific genetic mutation. The use of an external calibration with matrix-matched gelatin standards enables the quantification of iron by means of μXRF without the typically used fundamental parameters method or Monte Carlo simulation, which becomes more imprecise when analyzing thin tissue sections. A fast, non-destructive screening of the iron concentration and distribution with a spatial resolution of 25 μm in liver samples of iron-overload mice was developed. For improved limits of detection and higher spatial resolution down to 4 μm, LA-ICP-TQMS was used with oxygen as reaction gas. By monitoring the mass shift of Fe to FeO, a limit of detection of 0.5 μg/g was obtained. With this method, liver and pancreas samples of iron-overload mice as well as control mice were successfully analyzed. The high spatial resolution enabled the analysis of the iron distribution in different liver lobules. Compared to the established Prussian blue staining, both developed methods proved to be superior due to the possibility of direct iron quantification in the tissues.
遗传性血色素沉着症是最常见的铁代谢常染色体隐性遗传疾病。铁在各种器官中的积累，尤其是在肝脏和胰腺中，会导致疾病，并可能导致器官衰竭。在这项研究中，开发了元素生物成像的方法，通过定量微 X 射线荧光分析（μXRF）和激光烧蚀-电感耦合等离子体-三重四极杆质谱法（LA-ICP-TQMS），并应用于研究基于具有铁过载表型的动物的铁积累的病理生理发展，该动物具有由肝细胞特异性基因突变引起的铁过载表型。使用外部校准与基质匹配的明胶标准，使得可以通过μXRF 进行铁的定量，而无需通常使用的基本参数方法或蒙特卡罗模拟，当分析薄组织切片时，后者变得不太精确。开发了一种快速、非破坏性的筛选方法，用于对铁过载小鼠的肝脏样本进行铁浓度和分布的筛选，空间分辨率为 25μm。为了提高检测限和更高的空间分辨率，达到 4μm，使用 LA-ICP-TQMS 与氧作为反应气体。通过监测 Fe 到 FeO 的质量转移，可以获得 0.5μg/g 的检测限。使用这种方法，成功分析了铁过载小鼠和对照小鼠的肝脏和胰腺样本。高空间分辨率使我们能够分析不同肝小叶中的铁分布。与已建立的普鲁士蓝染色相比，由于可以直接在组织中进行铁定量，这两种方法都被证明具有优越性。
