Data underlying the publication: Preserving Full Spectrum Information in Imaging Mass Spectrometry Data Reduction

<strong>FT-ICR</strong>Human kidney tissue was surgically removed during a fullnephrectomy, and remnant tissue was processed for researchpurposes by the Cooperative Human Tissue Network (CHTN)at Vanderbilt University Medical Center. Human biospecimenswere collected in compliance with the CHTN protocols,institutional IRB policies, and the National Cancer Institute’sbest practices for procurement of remnant surgical researchmaterial. The tissue was flash-frozen over an isopentane-dryice slurry and embedded in carboxymethylcellulose. Tissuesections were cryosectioned with a thickness of 10 μm andthaw-mounted onto indium tin-oxide-coated glass slides (DeltaTechnologies, Loveland, CO, USA). 1,5-Diaminonaphthalene(DAN) was applied to the tissue surface using a TM Sprayer M3(HTX Technologies, Chapel Hill, NC, USA). The sample wasimaged (50 μm pitch) directly after matrix application witha 15T MALDI Fourier-transform ion cyclotron resonance (FT-ICR) mass spectrometer (Solarix, Bruker Daltonics, Billerica,MD, USA). Briefly, data were generated from m/z 300-2000with a 4M file size in negative ion mode.<br><strong>qTOF</strong>C57BL6/J mice were retro-orbitally infected with <em>S. aureus</em> Newman and sacrificed humanely five days post-infection. Kidneys were flash frozen on an isopentane/dry ice slurry and embedded in 2.6\% carboxymethylcellulose. 5 μm thick sections were collected using a Leica Biosystems CM3050S cryostat and thaw-mounted onto indium tin oxide coated glass slides. Sections were washed with cold 150 mM ammonium formate for 45 seconds for three total washes. 5 mg of 4-(dimethylamino)cinnamic acid matrix was applied using an in-house sublimation device. MALDI IMS data were collected in negative ion mode from m/z 400-2000 using a Bruker MALDI timsTOF fleX platform with a 5 μm step size, 25% laser power, and 25 shots per pixel.

<strong>傅里叶变换离子回旋共振（FT-ICR）</strong>
本研究采用的人体肾脏组织取自根治性肾切除术切除标本，剩余组织由范德堡大学医学中心合作人体组织网络（CHTN）按科研用途完成处理。人体生物样本的采集严格遵循CHTN操作规程、机构伦理审查委员会（IRB）政策以及美国国家癌症研究所关于残余手术科研材料获取的最佳实践规范。组织样本经异戊烷-干冰浴快速冷冻后，以羧甲基纤维素包埋。将组织以10 μm厚度进行冰冻切片，贴片于涂有氧化铟锡的载玻片（美国科罗拉多州拉夫兰市Delta Technologies公司产品）。使用TM Sprayer M3喷雾仪（美国北卡罗来纳州教堂山市HTX Technologies公司产品）将1,5-二氨基萘（DAN）基质喷涂于组织表面。基质喷涂完成后即刻采用15T基质辅助激光解吸电离-傅里叶变换离子回旋共振（MALDI-FT-ICR）质谱仪（布鲁克道尔顿公司Solarix型号，美国马萨诸塞州比勒里卡市），以50 μm的采样步距完成成像。简要而言，数据采集范围为m/z 300~2000，采用负离子模式，单文件大小为4M。
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<strong>四极杆飞行时间（qTOF）</strong>
C57BL6/J小鼠经眶后静脉注射感染金黄色葡萄球菌（S. aureus）Newman菌株，于感染后5天实施安乐死。肾脏组织经异戊烷/干冰浴快速冷冻后，以2.6%羧甲基纤维素包埋。使用徕卡生物系统CM3050S冰冻切片机制备5 μm厚的组织切片，贴片于氧化铟锡涂层载玻片。切片经冰冷的150 mM甲酸铵溶液漂洗三次，每次45秒。使用自制升华装置喷涂5 mg的4-(二甲氨基)肉桂酸基质。采用布鲁克MALDI timsTOF fleX平台，以5 μm步距、25%激光功率、每个像素采集25次激光脉冲，在负离子模式下采集m/z 400~2000范围的成像质谱（IMS）数据。