PROLIPHYC is a collaborative prospective study that aims at discovering deep cerebrospinal fluid (CSF) proteome with a new clinically-compatible proteomics strategy, in a cohort of 100 patients suspected of neurodegenerative diseases and/or normal pressure hydrocephalus.

CSF proteome is the real time protein content that may reveal useful biomarkers for diagnosis and therapeutic decision-making. But the low protein concentration in CSF and the low volumes typically obtained after lumbar puncture precludes the conventional use of proteomic analysis. We miniaturized the method to be compatible with low-volume samples by combination of nanoLC-MS/MS analysis and combinatorial peptide ligand library technology to reduce the dynamic range of protein concentration in CSF and unmask previously undetected proteins. We demonstrated that this deep proteomic analysis allows profiling the CSF proteome with a reasonable depth, in short analytical times and good accuracy. We settled a clinically-compatible proteomics strategy targeting the deep CSF proteome discovery.

The PROLIPHYC study is a prospective study that aims at analysing CSF proteome with our new strategy in a cohort of patients suspected of normal pressure hydrocephalus and/or related neurodegenerative diseases. The PROLIPHYC project combines detailed clinical and neuropsychological evaluation, gait analysis, MRI brain imaging, lumbar CSF dynamics and deep proteome. We hypothesize in the PROLIPHYC study that a specific cluster of polypeptides can be associated with Alzheimer disease, vascular dementia and normal pressure hydrocephalus profiles. Validating this hypothesis might be a significant step towards a proteomic lexicon of aging brain, neurodegenerative diseases and dementia.

Neurosciences department and Alzheimer disease centre from the Toulouse University Hospital are both involved in this project. The deep proteomic study is performed in Toulouse by the Institute of Pharmacology and Structural Biology with the academic support of the Institute of Mathematics of Toulouse.

Inclusion Criteria:

• Gait problems, cognitive decline, urinary incontinence and enlarged ventricles on imaging

Exclusion Criteria:

• Psychiatric disorders
• Lumbar punction contraindication
• RMI contraindication