Imaging Mass Spectrometry of Intact Biomolecules in Tissue Sections - Proteomic and Metabolomic Approaches to Biomarker Discovery - page 391

FIGURE 4 IMS abundance distributions obtained on a range of MALDI mass spectrometers for rat brain tissue sections (14
m m thick) coated with a solvent free dry matrix (CHCA). Raclopride brain tissue sections (i.v. 2.5 mg/kg) dose tissues (A)

analyzed by MALDI q-TOF at a spatial resolution of 100 m m. Abundance displayed on a heat-map scale. (B) Analyzed by

MALDI FT ICR at a spatial resolution of 100 m. (C) Pseudo-SRM images produced by mapping the distribution of the MSMS

fragmentation masses for raclopride m/z 347.0 to 129.1 (C.i) and 111.9 (C.ii) at a spatial resolution of 200

m

m performed on
a MALDI q-TOF. SCH 23390 brain tissue sections (iv, 5 mg/kg) (D) analyzed by MALDI q-TOF at a spatial resolution of 100
m

m

m. (F) Pseudo-
SRM image produced by mapping the distribution of the MSMS fragmentation masses for SCH 23390 m/z 289.1 to 179.0
abundance as heat-map scale (F.i) and monochrome red scale (F.ii) at a spatial resolution of 200

m. Abundance displayed on a heat-map scale. (E) analyzed by MALDI TOF at a spatial resolution of 200 m

m m performed on a MALDI q-

TOF. (Reprinted with permission from reference #73. Copyright 2011 American Chemical Society.)

sectioning of the tissue. 70,77 It is also important
that all sample preparation and data collection
parameters are kept constant throughout the
experiment to minimize nonbiological variability.
Recently we have shown the co-registration of
IMS and MRI in a murine model of staphylo-
coccus infection and treatment with linezolid. 77
Animals were infected retro-orbitally and the
infection allowed to progress for 96 hours before
treatment with 0.2 mg/mL of linezolid for 96
hours. The animals were splinted to prevent
movement and subjected to MRI measurements
of the abdomen. Large abscesses were observed
in the kidneys of untreated animals

organ or animal oftenwith co-registration to other
imaging modalities. This approach has been used
to create 3Dvolumes of the corpus callosum 74 and
the substantia nigra within the rodent brain. 75 Co-
registration of IMS with magnetic resonance
imaging (MRI) was shown in a xenograph model
of a human glioma in a rat brain. 76 Proteomic
data from imaged brain sections could be corre-
lated with data from noninvasive MR data.
Applications of IMS involving 3D imaging
require that many sections must be registered to
each other in order to construct a molecular
volume. Thus, it is necessary to minimize
any physical distortion of the samples during as