Abstract
RATIONALE: Previous studies have compared gene or protein expression from biopsies or random samples of IPF lung to normal or disease controls. Regional variation and typical progression of IPF provides a unique opportunity to investigate disease pathogenesis.
HYPOTHESIS: Region-specific cues from the microenvironment are central to the pathogenesis of IPF. Our aim was to examine the feasibility of conducting a qualitative and quantitative analysis of extracellular matrix proteins in human lung tissue using peptide sequencing and Maldi-imaging.
METHODS: Lung were air inflated to 20cm H20 pressure and snap frozen in liquid N2 fumes. Frozen slices were cut with a band saw and 2x2cm tissue cores prepared from 8 different regions. For Maldi imaging, sections (20 μm) were thaw mounted on indium tin oxide coated microscopic slides and coated with sinapinic acid. MS data were recorded on an Apex-Qe 12T hybrid quadrupole-FTICR mass spectrometer equipped with an Apollo dual-mode electrospray ionization Maldi ion source. Maldi imaging data were acquired with image pixel resolution of 200μm.