Neurofilaments: A Promising Diagnostic and Prognostic Biomarker in Multiple Sclerosis.

Background: Axonal damage results in permanent cognitive and physical disability during the early as well as progressive stages of multiple sclerosis (MS). However, the mechanism of axonal damage may vary during different stages of MS. The extent and severity of the disease can be estimated by various clinical tests and imaging. However, these measures lack sensitivity and accuracy for understanding subclinical disease activity. Therefore, there is a need for a promising biomarker that can reflect on clinical and subclinical disease activities and have additional diagnostic applications, such as studying MS pathology, disease severity, and rate of relapse. Summary: Neurofilaments (NFs) are released into the extracellular fluid following axonal insult, and hence, measuring them can help understand the severity of neuro-axonal damage, particularly during early stages of the disease. It can, therefore, serve as a promising biomarker in MS. Key Message: This review discusses NFs' biology and its correlation with disease activity, which may have clinical applicability in the diagnosis and prognosis of MS. Furthermore, their levels in response to treatment are also discussed, which can assist in the development of therapeutic strategies.