Title: High spatial resolution imaging of biological tissues using nanospray desorption electrospray ionization mass spectrometry

Abstract

Mass spectrometry imaging (MSI) enables label-free spatial mapping of hundreds of biomolecules in tissue sections. This capability provides valuable information on tissue heterogeneity that is difficult to obtain using population-averaged assays. Despite substantial developments in both instrumentation and methodology, MSI of tissue samples at single-cell resolution remains challenging. In our research, we describe a protocol for robust imaging of tissue sections with a high (better than 10-μm) spatial resolution using nanospray desorption electrospray ionization (nano-DESI) mass spectrometry, an ambient ionization technique that does not require sample pretreatment before analysis. In this protocol, mouse uterine tissue is used as a model system to illustrate both the workflow and data obtained in these experiments. We provide a detailed description of the nano-DESI MSI platform, fabrication of the nano-DESI and shear force probes, shear force microscopy experiments, spectral acquisition, and data processing. A properly trained researcher (e.g., technician, graduate student, or postdoc) can complete all the steps from probe fabrication to data acquisition and processing within a single day. We further describe a new strategy for acquiring both positive- and negative-mode imaging data in the same experiment. This is achieved by alternating between positive and negative data acquisition modes during consecutive line scans.more » Using our imaging approach, hundreds of high-quality ion images were obtained from a single uterine section. This protocol enables sensitive and quantitative imaging of lipids and metabolites in heterogeneous tissue sections with high spatial resolution, which is critical to understanding biochemical processes occurring in biological tissues.« less

Authors:

Yin, Ruichuan  ^[1];

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• Search DOE PAGES for ORCID "0000-0001-8478-7100"
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Burnum-Johnson, Kristin E.  ^[2];

• Search DOE PAGES for author "Burnum-Johnson, Kristin E."
• Search DOE PAGES for ORCID "0000-0002-2722-4149"
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Sun, Xiaofei  ^[3];

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• Search DOE PAGES for ORCID "0000-0001-9601-5423"
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Dey, Sudhansu K. ^[3]; Laskin, Julia  ^[4]

• Search DOE PAGES for author "Laskin, Julia"
• Search DOE PAGES for ORCID "0000-0002-4533-9644"
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+ Show Author Affiliations

1. Purdue Univ., West Lafayette, IN (United States)
2. Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
3. Univ. of Cincinnati, OH (United States)
4. Purdue Univ., West Lafayette, IN (United States); Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

Publication Date:

2019-11-13

Research Org.:

Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

Sponsoring Org.:

USDOE; National Institutes of Health (NIH)

OSTI Identifier:

1608770

Report Number(s):

PNNL-SA-142602
Journal ID: ISSN 1754-2189

Grant/Contract Number:  

AC05-76RL01830

Resource Type:

Accepted Manuscript

Journal Name:

Nature Protocols

Additional Journal Information:

Journal Volume: 14; Journal Issue: 12; Journal ID: ISSN 1754-2189

Publisher:

Nature Publishing Group

Country of Publication:

United States

Language:

English

Subject:

59 BASIC BIOLOGICAL SCIENCES