Brain-specific proteins in cerebrospinal fluid for the diagnosis of neurodegenerative diseases

Neurodegenerative disorders have traditionally been classified according to clinical criteria, e.g. as dementia syndromes (the best known is Alzheimer's disease) or as movement disorders (e.g. Parkinson's disease). Another subdivision is based on recent insights into the respective pathogenetic mechanisms, leading to the recognition of so-called tauopathies and alpha-synucleinopathies. It is this increased knowledge of the underlying (neuro)pathological mechanisms that has sparked interest in studies aimed at the identification of disease-specific biomarkers in cerebrospinal fluid (CSF) for this field of neurological disorders. This review deals with the recent progress that has been made in identification, quantification and subsequent validation of brain-specific proteins in CSF for the diagnosis of various neurodegenerative disorders. Development of disease-specific CSF biomarkers will undoubtedly add to the process of differential diagnosis early in the course of the disease.