Antibodies against light neurofilaments in multiple sclerosis patients

Objectives - Axonal damage in multiple sclerosis (MS) may be reflected by antibodies against axon-specific proteins - the light subunit of neurofilaments (NFL). Materials and methods - The serum and cerebrospinal fluid obtained from 58 MS patients, 24 normal controls (CN), 49 control patients with miscellaneous diseases (CD) and 31 patients with neurodegenerative disorders (CDEG) were tested for both immunoglobulin G and M antibodies against NFL, using an ELISA. Results - Intrathecal IgG antibodies to NFL were elevated in MS patients compared with that in CD patients (P = 0.001) and were not related to clinical variables. No differences in IgM anti-NFL levels were found between the MS and CN/CD groups. IgM to NFL was higher in the CDEG group than in either the CD group or even the MS group (P < 0.0005). Conclusions - Intrathecal IgM or IgG antibodies to NFL are not useful surrogate markers for axonal damage or disease subtypes in MS.