Introduction/Objectives:
An important contribution of B cells and autoantibodies has been demonstrated in the pathogenesis of multiple sclerosis (MS) leading to interest in the use of such autoantibodies as diagnostic or prognostic markers. A common problem in studies of humoral immunity is that accurate detection of antibodies depends highly on the conformation of the antigens used for detection. Therefore widely used techniques, including ELISA and Western blotting, may fail to detect reactivity against epitopes displayed by native antigens expressed on myelin sheats. Here we describe a cell-based assay that specifically identifies serum antibodies directed against three major myelin autoantigens: MBP, PLP and MOG. The proposed method detects antibody binding to recombinant antigens in their native conformation on MBP, PLP and MOG transfected mammalian (hamster ovary) cells.
Material and methods:
Thirty-six patients with relapsing-remitting MS diagnosed according to criteria of Mc Donald were recruted. Age 38.2 and duration of the disease 7.1. Serum anti-MBP, anti-PLP and anti-MOG IgG autoantibodies were detected in MS patients and 35 healthy donors by FACS analysis.
Results:
Compared with healthy controls the titers of IgG autoantibodies directed against membrane-bound recombinant myelin antigens were most significantly increased for PLP (P < 0.0001), no quite significant for MBP (P < 0.05) and not significant for MOG (P < 0.7). The titers of anti-MBP antibodies were low indicating low concentration of these Ab in serum of MS patients and healthy donors, in contrast to high titers of anti-MOG antibodies in both groups suggesting a non-specific binding.
Conclusions:
The cell-based assay detection of autoantibodies directed against recombinant myelin antigens could be a useful tool providing the serological markers in diagnosis and progression of MS. Indeed, it could allow to obtain molecular characteristics of disease in each patient in term of an antibody response against certain myelin and non-myelin antigens. We have shown that in RRMS patients elevated level of serum antibodies against PLP is significant, what should be considered in search for specific immunomodulatory therapy in MS.
