Imaging mass spectrometry analysis of renal amyloidosis biopsies reveals protein co-localization with amyloid deposits
Imaging mass spectrometry analysis of renal amyloidosis biopsies reveals protein co-localization with amyloid deposits
复制标题
DOI：
10.1007/s00216-015-8689-z
复制
发表时间：
2015-07-01
影响因子：
4.3
通讯作者：
Kriegsmann, Joerg
中科院分区：
文献类型：
--
作者：
Casadonte, Rita;Kriegsmann, Mark;Kriegsmann, Joerg
淀粉样变性是一种以淀粉样蛋白沉积为特征的蛋白质错误折叠疾病。肾脏经常受到影响，尤其是免疫球蛋白轻链（AL）和血清淀粉样蛋白A （SAA）淀粉样变性是最常见的亚群。目前的诊断依赖于组织病理学检查、刚果红染色或电子显微镜。通过免疫组织化学进行分型；然而，市售抗体缺乏特异性。本研究的目的是利用基质辅助激光解吸/电离成像质谱（MALDI IMS）结合液相色谱-串联质谱（LC-MS/MS）分析，在一个集成的工作流程中鉴定和绘制福尔马林固定石蜡包埋组织切片中的淀粉样蛋白。对肾脏淀粉样变和非淀粉样变活检进行组织学和质谱分析。亲嗜血区对应的质谱直接与组织学和质谱图联系起来进行相关性研究。用MALDI IMS检测刚果红阳性区相关的SAA和AL肽。采用LC-MS/MS法测定淀粉样蛋白肽序列，提供蛋白质分布和鉴定。AA和AL淀粉样变性患者血清淀粉样蛋白P组分、载脂蛋白E和玻璃体连接蛋白均与刚果红阳性区密切相关。我们的研究结果强调了MALDI IMS作为一种新的方法在组织病理学常规材料中分型淀粉样变性，并表征淀粉样相关蛋白，这可能为淀粉样蛋白形成的病理过程提供见解。
Amyloidosis is a heterogeneous group of protein misfolding diseases characterized by deposition of amyloid proteins. The kidney is frequently affected, especially by immunoglobulin light chain (AL) and serum amyloid A (SAA) amyloidosis as the most common subgroups. Current diagnosis relies on histopathological examination, Congo red staining, or electron microscopy. Subtyping is done by immunohistochemistry; however, commercially available antibodies lack specificity. The purpose of this study was to identify and map amyloid proteins in formalin-fixed paraffin-embedded tissue sections using matrix-assisted laser desorption/ionization imaging mass spectrometry (MALDI IMS) coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis in an integrated workflow. Renal amyloidosis and non-amyloidosis biopsies were processed for histological and MS analysis. Mass spectra corresponding to the congophilic areas were directly linked to the histological and MS images for correlation studies. Peptides for SAA and AL were detected by MALDI IMS associated to Congo red-positive areas. Sequence determination of amyloid peptides by LC-MS/MS analysis provided protein distribution and identification. Serum amyloid P component, apolipoprotein E, and vitronectin proteins were identified in both AA and AL amyloidosis, showing a strong correlation with Congo red-positive regions. Our findings highlight the utility of MALDI IMS as a new method to type amyloidosis in histopathological routine material and characterize amyloid-associated proteins that may provide insights into the pathogenetic process of amyloid formation.