Focused Proteomics in Post-Mortem Human Spinal Cord

Abstract

With a highly sensitive electrospray ionization−Fourier transform ion cyclotron resonance mass spectrometry (ESI−FTICR MS) system, proteins were identified in minimal amounts of spinal cord from patients with the neurodegenerative disease amyotrophic lateral sclerosis (ALS) and compared to proteins in spinal cord from control subjects. The results show 18 versus 16 significantly identified ( p < 0.05) proteins, respectively, all known to be found in the central nervous system. The most abundant protein in both groups was the glial fibrillary acidic protein, GFAP. Other proteins were, for example, hemoglobin α- and β chain, myelin basic protein, thioredoxin, α enolase, and cholin acetyltransferase. This study also includes the technique of laser microdissection in combination with pressure catapulting (LMPC) for the dissection of samples and specific neurons. Furthermore, complementary experiments with nanoLC-matrix assisted laser desorption ionization time-of-flight tandem mass spectrometry (MALDI-TOF-TOF MS) confirmed the results of the ESI−FTICR MS screening and provided additional results of further identified proteins. Keywords: proteomics • electrospray ionization−Fourier transform ion cyclotron resonance mass spectrometry (ESI−FTICR MS) • matrix-assisted laser desorption ionization time-of-flight tandem mass spectrometry (MALDI-TOF-TOF MS) • neurodegeneration • amyotrophic lateral sclerosis • spinal cord • laser microdissection with pressure catapulting (LMPC)