Dataset Information

Viral biomarker detection and validation using MALDI Mass Spectrometry Imaging (MSI)

ABSTRACT: INTRODUCTION: Mass Spectrometry Imaging (MSI) is a hybrid mass spectrometry technique that integrates aspects of traditional microscopy and mass spectrometry-based omics analysis. The traditional MALDI TOF/TOF instrument still remains the dominant platform for this type of anal-ysis. However, with reduced mass resolution compared to other platforms it is insufficient to rely on mass resolution alone for peptide identification. Here we propose a hybrid method of data analysis that integrates both image-based analysis and a parallel protein identification workflow using peptide mass fingerprinting, and its successful application to the detection and validation of viral biomarkers. METHODS: FFPE samples were imaged as described previously in an UltrafleXtreme MALDI TOF/TOF. Total mass spectra were exported and searched against the mouse FASTA da-tabase, while companion images were exported and processed with image J. RESULTS: Peptide mass fingerprinting (PMF) revealed 14 target peptides that were successfully assigned to viral proteins while a pixel based correlational analysis revealed a very high R2 correlation (>0.81) be-tween those same peptides assigned to the NS1 and VP1 viral proteins. CONCLUSIONS: We successfully identified and validated the presence of viral biomarkers to a high degree of confidence using MALDI MSI.

INSTRUMENT(S): ultraflex

ORGANISM(S): Mus Musculus (mouse)

TISSUE(S): Kidney

SUBMITTER: Matthew O'Rourke

LAB HEAD: Phil P Hansbro

PROVIDER: PXD034851 | Pride | 2022-10-13

REPOSITORIES: Pride

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			Action	DRS
	20180313_UFX_MOR_658_IMG_A.bak	Other
	20180313_UFX_MOR_658_IMG_A.dat	Other
	20180313_UFX_MOR_658_IMG_A.imzML	Other
	20180313_UFX_MOR_658_IMG_A.mis	Other
	checksum.txt	Txt

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Viral Biomarker Detection and Validation Using MALDI Mass Spectrometry Imaging (MSI).

O'Rourke Matthew B MB Roediger Ben R BR Jolly Christopher J CJ Crossett Ben B Padula Matthew P MP Hansbro Phillip M PM

Proteomes 20220913 3

(1) Background: MALDI imaging is a technique that still largely depends on time of flight (TOF)-based instrument such as the Bruker UltrafleXtreme. While capable of performing targeted MS/MS, these instruments are unable to perform fragmentation while imaging a tissue section necessitating the reliance of MS1 values for peptide level identifications. With this premise in mind, we have developed a hybrid bioinformatic/image-based method for the identification and validation of viral biomarkers. ( ...[more]

PMID: 36136311

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