Altered expression and glycosylation of plasma proteins in rheumatoid arthritis.

Altered glycosylation of plasma proteins has been directly implicated in the pathogenesis of rheumatoid arthritis (RA). The present study investigated the changes in the Concanavalin-A (Con-A)-bound plasma proteins in the RA patients in comparison to that of the healthy controls. Two proteins (MW approximately 32 kDa and approximately 62 kDa) showed an alteration in expression while an altered monosaccharide profile (high mannose) was observed in the approximately 62 kDa protein in the samples collected from RA patients. The 2-dimensional polyacrylamide gel electrophoresis analysis of the Con-A-bound plasma samples showed a large number of protein spots, a few of which were differentially expressed in the RA patients. Some unidentified proteins were detected in the RA patients which were absent in the control samples. The present study, therefore, enunciates the role of carbohydrates as well as that of the acute phase response in the disease pathogenesis.