Send to

Choose Destination
Proteomics. 2016 Apr;16(7):1154-65. doi: 10.1002/pmic.201500284.

Label-free analysis of human cerebrospinal fluid addressing various normalization strategies and revealing protein groups affected by multiple sclerosis.

Author information

Proteomics Unit (PROBE), Department of Biomedicine, University of Bergen, Bergen, Norway.
The KG Jebsen Centre for MS-research, Department of Clinical Medicine, University of Bergen, Bergen, Norway.
Neurology Department, Cliniques Universitaires Saint-Luc, Université Catholique de Louvain, Brussels, Belgium.
Laboratory of Neuroimmunology, IRCCS, "C. Mondino" National Neurological Institute, Pavia, Italy.
Department of Clinical Science, University of Bergen, Bergen, Norway.
Surgical Clinic, Haukeland University Hospital, Bergen, Norway.
The Norwegian Multiple Sclerosis Competence Centre, Department of Neurology, Haukeland University Hospital, Bergen, Norway.


The aims of the study were to: (i) identify differentially regulated proteins in cerebrospinal fluid (CSF) between multiple sclerosis (MS) patients and non-MS controls; (ii) examine the effect of matching the CSF samples on either total protein amount or volume, and compare four protein normalization strategies for CSF protein quantification. CSF from MS patients (n = 37) and controls (n = 64), consisting of other noninflammatory neurological diseases (n = 50) and non neurological spinal anesthetic subjects (n = 14), were analyzed using label-free proteomics, quantifying almost 800 proteins. In total, 122 proteins were significantly regulated (p < 0.05), where 77 proteins had p-value <0.01 or AUC value >0.75. Hierarchical clustering indicated that there were two main groups of MS patients, those with increased levels of inflammatory response proteins and decreased levels of proteins involved in neuronal tissue development (n = 30), and those with normal protein levels for both of these protein groups (n = 7). The main subgroup of controls clustering with the MS patients showing increased inflammation and decreased neuronal tissue development were patients suffering from chronic fatigue. Our data indicate that the preferable way to quantify proteins in CSF is to first match the samples on total protein amount and then normalize the data based on the median intensities, preferably from the CNS-enriched proteins.


Biomarker; Biomedicine; Inflammation; Label free; Multiple sclerosis; Neurodegeneration

[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Wiley
Loading ...
Support Center