Cerebrospinal fluid proteome profile in multiple sclerosis.

Cerebrospinal fluid (CSF) proteins may provide important information about the pathomechanisms present in multiple sclerosis (MS). Although diagnostic criteria for early MS are available, there is still a need for biomarkers, predicting disease subtype and progression to improve individually tailored treatment. Using the two-dimensional difference gel electrophoresis (2-D-DIGE) technology for comparative analysis, we compared CSF samples from patients with MS of the relapse-remitting type (RRMS, n = 12) and from patients with clinically isolated syndrome (CIS, n = 12) suggestive of a first demyelinating attack with neurologically normal controls. Protein spots that showed more than two-fold difference between patients and controls were selected for further analysis with MALDI-TOF mass spectrometry. Immunoblot analysis was performed to confirm the validity of individual candidate proteins. In RRMS, we identified 1 up-regulated and 10 down-regulated proteins. In CIS, 2 up-regulated and 11 down-regulated proteins were identified. One of these proteins (Apolipoprotein A1) was confirmed by immunoblot. Though the pathophysiological role of these proteins still remains to be elucidated in detail and further validation is needed, these findings may have a relevant impact on the identification of disease-specific markers.