INTRODUCTION: Antibodies against mutated citrullinated @entity2277 ( @entity68072 ) represent a useful diagnostic marker with correlation to disease activity in @entity1 with @entity309 ( @entity309 ). Since seropositivity for citrullinated autoantibodies was predictive for response to B-cell depleting therapy (BCDT) with rituximab (RTX), we investigated whether differences in antibody fine reactivity and immunoglobulin (Ig) isotype kinetics among @entity68072 -positive @entity1 could provide additional information about outcome. METHODS: A total of 50 AMCV IgG-positive @entity309 @entity1 (RTX responders (RRs) n = 37 and non-responders (NRRs) n = 13) were analyzed for reactivity against MCV epitopes and co-existent @entity68072 isotypes IgM and IgA. Antibody titers were determined by enzyme-linked immunosorbent assay at baseline and 24 weeks after the first cycle of RTX, and compared to kinetics of rheumatoid factor (RF) and antibodies against cyclic citrullinated peptide (ACCP). RESULTS: Recognized MCV epitopes by AMCV IgG of RRs and NRRs showed similar baseline patterns, with reducing reactivity in RRs and unchanged or even expanding reactivity in NRRs upon RTX treatment. At baseline, RRs were more frequently negative for @entity68072 subtypes, especially for IgA (68 %), compared to NRRs (31 %). Being @entity68072 IgA-negative at baseline indicated a good treatment response to RTX (negative predictive value = 0.86). Co-existence of @entity68072 IgA and IgG with stable titers upon treatment were associated with poorer responses to RTX. Furthermore, reductions of @entity68072 IgA levels upon RTX correlated with the improvement of 28-joint Disease Activity Score (DAS28). In comparison, subtypes of RF and ACCP were not of additional value for prediction of RTX response. CONCLUSIONS: Restrictive IgG seropositivity against MCV with treatment-associated decline in fine reactivity and titers was predictive for response to RTX. Double-positivity for AMCV IgG and IgA was associated with failure to respond to BCDT, suggesting a pathogenetic and less sensitive IgA-producing B-cell subset in NRRs.

Restrictive IgG antibody response against mutated citrullinated XXXX predicts response to rituximab in @entity1 with @entity309 .

@entity1 :: ('9606', 'Species') :: ['patients'] @entity68072 :: ('12142', 'Species') :: ['AMCV'] @entity2277 :: ('7431', 'Gene') :: ['vimentin'] @entity309 :: ('MESH:D001172', 'Disease') :: ['rheumatoid arthritis', 'RA']
@entity2277 :: (7431,Gene) :: ['vimentin']
