Multiple Sclerosis Serum Biomarker Predictive of Disability and Disease Activity

Investigators used a highly sensitive single-molecule array assay suitable for use in blood rather than cerebrospinal fluid (CSF). Previously, CSF-based assays were required because serum neurofilament light chain (sNfL) concentration is 42-fold lower than in CSF. This study included a longitudinal cohort of 246 multiple sclerosis (MS) patients, a cross-sectional cohort of 142 MS patients who also had CSF available for comparison, and 254 healthy controls.

Serum NfL levels correlated well with CSF NfL (r=0.8, P<0.001) and increased with increasing numbers of T2 and enhancing lesions in brain and spinal cord. Serum NfL level also was independently associated with Expanded Disability Status Scale score and recent relapse and inversely with tim…