Osteopontin levels and increased disease activity in relapsing-remitting multiple sclerosis patients

Osteopontin (OPN) has been identified as the most prominent cytokine-encoding gene expressed within multiple sclerosis (MS) lesions. Recently, we demonstrated that OPN plasma levels were elevated in active relapsing-remitting (RR) MS patients. In this longitudinal study, a trend was observed for OPN serum levels in relation to clinical exacerbations. Moreover, OPN protein levels were significantly elevated 1 month prior to increase of gadolinium (Gd)-enhancing lesion number, whereas no relation was observed between OPN levels and increase in Gd-enhancing lesion volume. Although no robust relation between OPN and disease activity was observed, these data suggest that OPN levels are elevated prior to increased disease activity in RR MS patients.