Serum matrix metalloproteinase-3 levels correlate with disease activity in relapsing-remitting multiple sclerosis

Background: Adhesion molecules and matrix metalloproteinases. (MMPs) are known to be relevant to the ongoing development and disappearance of areas of demyelination in the white matter of the CNS of multiple sclerosis (MS) patients. This study examined whether serum matrix metalloproteinase-3 (MMP-3) levels correlate with disease activity in MS. Methods: Serum MMP-3 levels in 47 consecutive patients with relapsing-remitting MS were measured by immunoassay every A weeks over a 15 month period. Results: During the study period, 48 clinical relapses occurred. Serum MMP-3 levels within 1 month of relapse were significantly higher than during the remission phase. Sequential analysis showed that serum MMP-3 levels had increased transiently at the time of clinical relapse but returned to the normal range within a month. Conclusions: Circulatory MMP-3 levels are correlated with disease activity in relapsing-remitting MS. This may contribute to the breakdown of the blood-brain barrier at the time of relapse.