The CXCL13 Index as a Predictive Biomarker for Activity in Clinically Isolated Syndrome.

Multiple sclerosis (MS) is a clinically heterogenous disease. Currently, we cannot identify patients with more active disease who may potentially benefit from earlier interventions. Previous data from our lab identified the CXCL13 index (I CXCL13 ), a measure of intrathecal production of CXCL13, as a potential biomarker to predict future disease activity in MS patients two years after diagnosis. Patients with clinically isolated syndrome (CIS) or radiologically isolated syndrome (RIS) underwent a lumbar puncture and blood draw, and the I CXCL13 was determined. They were then followed for at least 5 years for MS activity. Patients with high I CXCL13 were more likely to convert to clinically definite MS (82.4%) compared to those with low I CXCL13 (10.0%). The data presented below demonstrate that this predictive ability holds true in CIS and RIS patients, and for at least five years compared to our initial two-year follow-up study. These data support the concept that I CXCL13 has the potential to be used to guide immunomodulatory therapy in MS.