Cytoskeletal proteins in the cerebrospinal fluid as biomarker of multiple sclerosis

The axonal cytoskeleton is a finely organized system, essential for maintaining the integrity of the axon. Axonal degeneration is implicated in the pathogenesis of unremitting disability of multiple sclerosis (MS). Purpose of this study is to evaluate levels of cytoskeletal proteins such as neurofilament light protein (NFL), glial fibrillary acidic protein (GFAP), and β-tubulin (β-Tub) isoforms II and III in the cerebrospinal fluid (CSF) of MS patients and their correlation with MS clinical indices. CSF levels of cytoskeletal proteins were determined in 51 patients: 33 with MS and 18 with other neurological diseases (OND). NFL, GFAP and β-Tub II proteins were significantly higher (p < 0.0001) in MS than in OND group; no significant difference (p > 0.05) was found between MS and OND with regard to β-Tub III. Interestingly, levels of β-Tub III and NFL were higher in progressive than in remitting MS forms; on the contrary, higher levels of β-Tub II and GFAP were found in remitting MS forms. However, with the exception of β-Tub III, all proteins tend to decrease their CSF levels concomitantly with the increasing disability (EDSS) score. Overall, our results might indicate β-Tub II as a potential candidate for diagnostic and β-Tub III as a possible prognostic biomarker of MS. Therefore, further analyses are legitimated and desirable.