The characterization of anti-carbamylated protein antibodies in rheumatic diseases : isotype usage, avidity and molecular composition

The scope of this thesis is to describe the immunological characteristics and molecular composition of anti-CarP antibodies in rheumatoid arthritis, as well as the presence of anti-CarP antibodies in relation to bone erosions on diseases other than RA. This thesis is subdivided in three parts.Part 1: Characterisation of the anti-CarP antibody response in rheumatoid arthritisBoth ACPA and anti-CarP antibodies are present in RA.We describe the examination of the anti-CarP antibody response in RA by means of isotype and IgG-subclass usage in baseline serum samples of RA-patients as well as by means of the avidity of anti-CarP antibodies. Moreover, the anti-CarP IgG V-domain glycosylation was studied.Part 2: Possibilities for a mucosal origin of autoantibodies in rheumatoid arthritisSeveral lines of evidence obtained in the recent years indicate a role for mucosal surfaces in the development of auto-immune responses associated with RA. Therefore, we studied the molecular composition of RA associated IgA autoantibodies.Part 3: anti-CarP antibodies in other rheumatic diseases that can be characterized by bone erosionsBecause anti-CarP antibodies and ACPAs are also present in other clinical conditions than RA, we investigated their presence and association with bone erosions in Systemic Lupus Erythematosus and hand osteorthritis.