Prospective exploration of biochemical tissue composition via imaging mass spectrometry guided by principal component analysis.
MALDI-based Imaging Mass Spectrometry (IMS) is an analytical technique that provides the opportunity to study the spatial distribution of biomolecules including proteins and peptides in organic tissue. IMS measures a large collection of mass spectra spread out over an organic tissue section and retains the absolute spatial location of these measurements for analysis and imaging. The classical approach to IMS imaging, producing univariate ion images, is not well suited as a first step in a prospective study where no a priori molecular target mass can be formulated. The main reasons for this are the size and the multivariate nature of IMS data. In this paper we describe the use of principal component analysis as a multivariate pre-analysis tool, to identify the major spatial and mass-related trends in the data and to guide further analysis downstream. First, a conceptual overview of principal component analysis for IMS is given. Then, we demonstrate the approach on an IMS data set collected from a transversal section of the spinal cord of a standard control rat.
Van de Plas
Raf
R
Katholieke Universiteit Leuven, Department of Electrical Engineering (ESAT), SCD-SISTA (BIOI), Kasteelpark Arenberg 10, B-3001 Leuven (Heverlee), Belgium. raf.vandeplas@esat.kuleuven.be
Ojeda
Fabian
F
Dewil
Maarten
M
Van Den Bosch
Ludo
L
De Moor
Bart
B
Waelkens
Etienne
E
D000818:Animals; D019295:Computational Biology; D007091:Image Processing, Computer-Assisted / Q000706:statistics & numerical data*; D009419:Nerve Tissue Proteins / Q000378:metabolism; D025341:Principal Component Analysis; D011506:Proteins / Q000378:metabolism*; D051381:Rats; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000706:statistics & numerical data*; D013116:Spinal Cord / Q000378:metabolism; D014018:Tissue Distribution
D009419:Nerve Tissue Proteins; D011506:Proteins