Integrated analysis of the cerebrospinal fluid peptidome and proteome

J Proteome Res. 2008 Jan;7(1):386-99. doi: 10.1021/pr070501k. Epub 2007 Dec 4.


Cerebrospinal fluid (CSF) is the only body fluid in direct contact with the brain and thus is a potential source of biomarkers. Furthermore, CSF serves as a medium of endocrine signaling and contains a multitude of regulatory peptides. A combined study of the peptidome and proteome of CSF or any other body fluid has not been reported previously. We report confident identification in CSF of 563 peptide products derived from 91 precursor proteins as well as a high confidence CSF proteome of 798 proteins. For the CSF peptidome, we use high accuracy mass spectrometry (MS) for MS and MS/MS modes, allowing unambiguous identification of neuropeptides. Combination of the peptidome and proteome data suggests that enzymatic processing of membrane proteins causes release of their extracellular parts into CSF. The CSF proteome has only partial overlap with the plasma proteome, thus it is produced locally rather than deriving from plasma. Our work offers insights into CSF composition and origin.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cerebrospinal Fluid Proteins / analysis*
  • Humans
  • Membrane Proteins / metabolism
  • Neuropeptides / analysis*
  • Peptide Hydrolases / metabolism
  • Peptides / analysis
  • Proteomics / methods*
  • Spinal Puncture
  • Tandem Mass Spectrometry


  • Cerebrospinal Fluid Proteins
  • Membrane Proteins
  • Neuropeptides
  • Peptides
  • Peptide Hydrolases