OBJECTIVES Events in the lungs might contribute to generation of anticitrullinated protein antibodies (ACPA) in rheumatoid arthritis (RA). We investigated if signs of immune activation are present in bronchial biopsies and bronchoalveolar lavage (BAL) of patients with early-untreated RA without clinical signs of lung involvement. METHODS Twenty-four patients with RA with symptom duration <1 y...

BACKGROUND Rheumatoid arthritis (RA) is an autoimmune disease of the synovial joints. The autoimmune character of RA is underscored by prominent production of autoantibodies such as those against IgG (rheumatoid factor), and a broad array of joint tissue-specific and other endogenous citrullinated proteins. Anti-citrullinated protein antibodies (ACPA) can be detected in the sera and synovial fl...

INTRODUCTION The aim of this study was to characterize anti-citrullinated peptide antibody (ACPA) serostatus in pre-clinical rheumatoid arthritis (RA) with and without Human Leukocyte Antigen-Shared Epitope (HLA-SE) alleles. METHODS We identified 192 women in the Nurses' Health Study cohorts with blood samples obtained 4 months to 17 years prior to medical record-confirmed RA diagnosis. Three...

OBJECTIVES Anticarbamylated protein (anti-CarP) antibodies are a novel family of autoantibodies recently identified in patients with inflammatory arthritis. The aim of this study was to investigate their association with long-term outcomes of disability and disease activity over 20 years' follow-up in a cohort of patients with inflammatory polyarthritis (IP). METHODS Norfolk Arthritis Registe...

Anticitrullinated peptide/protein antibodies (ACPA), which are highly specific for rheumatoid arthritis (RA), may be found in some patients with other systemic autoimmune diseases. The clinical significance of ACPA in patients with antisynthetase syndrome (ASS), a systemic disease characterized by the association of myositis, interstitial lung disease, polyarthralgia, and/or polyarthritis, has ...

IgM ACPA 6 (20) 11 (37) 13 (43) Introduction We and others have previously shown that the development of rheumatoid arthritis (RA) is preceded by IgG anti-citrullinated protein antibody (ACPA) and rheumatoid factor (RF) [1,2]. Furthermore, it was shown that other isotypes of ACPA (IgA and, to a lesser extent, the IgM isotype) also predate the onset of RA [3]. Moreover, smoking has been linked t...

BACKGROUND To analyze differences in the recognition of anti-citrullinated peptide/protein antibody (ACPA) citrullinated epitopes and isotypes in patients with palindromic rheumatism (PR) and rheumatoid arthritis (RA). METHODS ACPA fine specificities (citrullinated peptides of enolase, fibrin, and vimentin) and isotypes (IgG, IgM, and IgA) were analyzed in 54 patients with longstanding PR and...

BACKGROUND Several anticitrullinated protein/peptide antibodies (ACPA) assays have been reported to be of diagnostic value for rheumatoid arthritis (RA). We evaluated the technical performance and diagnostic accuracy of 6 ELISAs for the detection of antibodies to citrullinated protein/peptide antigens. METHODS ACPA were determined in 298 serum samples using 6 commercially available ACPA assay...

18 Background: In rheumatoid arthritis (RA), anti-citrullinated protein/peptide antibodies (ACPAs) 19 are responsible for disease onset and progression, however, our knowledge is limited on ligand 20 binding affinities of autoantibodies with different citrulline-peptide specificity. 21 Methods: Citrulline-peptide specific ACPA IgGs were affinity purified and tested by ELISA. 22 Binding affiniti...