Influence of oligoclonal IgM specificity in XXXX .

@entity1 @entity15
Oligoclonal IgM bands (OCMB) against myelin lipids predict an aggressive @entity15 ( @entity15 ) course. However, the clinical significance of OCMB without lipid specificity, present in other @entity15 @entity1 , remains unknown. We describe here a characterization of these antibodies and study their role in @entity15 progression. Fifty-four @entity15 @entity1 showing CSF-restricted OCMB were included in this study at disease onset and followed-up during 61.1 +/- 2.7 months. The specificity of OCMB and the CSF B-cell profile were investigated. A second CSF IgM study was performed in a group of eight @entity1 . Thirty-eight @entity1 showed OCMB against myelin lipids (M+L+) and other sixteen had OCMB lacking this specificity (M+L-). The CD5+ B cell subpopulation, responsible for most persistent IgM responses, was considerably higher in M+L+ than in M+L- @entity1 (3.3 +/- 0.6% versus 0.8 +/- 0.2, P = 0.009). In addition, M+L+ bands persisted during disease course, while M+L- disappeared during follow-up. M+L+ @entity1 suffered more relapses (4.2 +/- 0.6 versus 1.6 +/- 0.3, P = 0.002) and reached higher disability (EDSS score of 2.2 +/- 0.2 versus 1.2 +/- 0.2, P = 0.02) than M+L- group. These data corroborate that anti-lipid OCMB associate with an aggressive @entity15 course and show that OCMB that do not recognize myelin lipids represent a transient immune response related to a more benign disease course.
