A Novel Method of Tissue Collection and Storage: Validation Using SELDI-TOF MS Analysis

Bouamrani et al. (1) recently reported an approach to SELDI-TOF mass spectrometry that uses direct apposition of cryosections onto proteinchips to enrich spectral profiles and improve the discriminatory power of the technique. To prevent protein degradation, however, samples must be stored frozen and locally processed or shipped frozen to a proteomics facility. We have found that tissue can be preserved on filter paper in a way that maintains the protein profiles obtained with frozen tissues and allows targeted tissue analysis and storage at room temperature. We use a type of filter paper routinely used for body fluid sample collection, transport, and archiving for various analyses (2). We used serial coronal sections from frozen rat brains at the caudate-putamen (CP) level (anteroposterior: 0.70 mm from bregma) to compare nonpaper- and paper-collection methods. Nonpaper methods comprised 2 different techniques, tissue apposition (TA) and tissue lysate (TL). For TA, 4 mm2 of the CP area was isolated from 10-μm cryosections and apposed onto an NP20 proteinchip. For TL, a similar 4-mm2 sample was inserted into an Eppendorf tube and 20 μL lysis buffer (LB) or distilled water (dH2O) was added, vortex-mixed (30 s), left 10 min on ice, centrifuged, and then 2 μL of the supernatant was pipetted onto the …