Brainy solution

Cerebrospinal fluid (CSF) acts as a barrier to cushion the brain and spine, protecting them from bumps as well as providing immunological protection. Knowledge of the proteins present, absent or changing within the CSF could lead to diagnostic, prognostic or disease-activity biomarkers for neurologic and psychiatric disorders. A comprehensive analysis has been difficult up to this point because of the low protein levels in CSF compared with plasma, the potential masking of brain-specific proteins by other highly abundant proteins and limited access to samples from healthy individuals. However, a study published in PLoS ONE¹ has provided the most comprehensive protein profile to date, using liquid chromatography to identify 2630 proteins, nearly three times the number previously identified.

Immunoaffinity separation was applied to the samples before they were analysed using reversed-phase capillary LC–MS–MS and LC–MS. According to the study, this method and approach differed from previous attempts as it included a rigorous separation of abundant and less abundant proteins to combat the masking effect, as well as high-resolution LC–MS–MS for highly efficient peptide identification. The authors expect that the availability of this data will provide a critical base for the qualitative and quantitative comparison of proteins in the future.

^{1. S.E. Schutzer et al., PLoS ONE, 5(6) (2010).}

This story originally appeared in The Column. Click here to view that issue.