Autoantibodies can be prognostic markers of an erosive disease in early rheumatoid arthritis.

OBJECTIVE: To evaluate a contribution of selected laboratory parameters for a prediction of progressive and erosive development in patients with early rheumatoid arthritis (RA). METHODS: In a prospective study baseline levels of antibodies to cyclic citrullinated peptide (anti-CCP), IgM, IgA, and IgG rheumatoid factors (RFs) were measured by enzyme linked immunosorbent assay (ELISA) in 104 patients with RA with disease duration <2 years. Antikeratin antibodies (AKA) and antiperinuclear factor (APF) were detected by indirect immunofluorescence. Patients were divided into two groups based either on the presence or absence of erosions or according to progression of Larsen score at the end of the 24 months' follow up. RESULTS: Sixty seven (64%) patients developed radiographic erosions, 49 (47%) had progression in Larsen score, and 36 (35%) progressed by more than 10 Larsen units. Significant differences in erosions and progression between the two groups were detected for anti-CCP, AKA, APF, IgM RF, IgA RF, and IgG RF. Baseline Larsen score correlated significantly with anti-CCP, IgM RF, and IgA RF levels, and all measured antibodies correlated with the progression >10 units. The combination of anti-CCP and IgM RF increased the ability to predict erosive and progressive disease. CONCLUSION: The data confirmed that measurement of anti-CCP, AKA, APF, and individual isotypes of RFs was useful for prediction of structural damage early in the disease course. Combined analysis of anti-CCP and IgM RF provides the most accurate prediction.

Cyclosporine A versus methotrexate in the treatment of polymyositis and dermatomyositis.

OBJECTIVE: To determine the effectiveness and tolerance of treatment with cyclosporine A (CyA) or methotrexate (MTX) added to corticosteroids in patients with severe, active polymyositis (PM) and dermatomyositis (DM). PATIENTS AND METHODS: Thirty-six patients (20 with DM, 16 with PM) were enrolled into the study and randomized in MTX (n = 17) and CyA (n = 19) groups. Muscle endurance and functional test (MEFT), clinical assessment (CA), global patient's assessment (GPA), muscle MRI, serum CK, myoglobin, IL-1Ra, and autoantibody status were used to assess the response to therapy after 1, 3, and 6 months. RESULTS: Significant improvement in MEFT, CA, GPA, and muscle MRI was found in both groups. Patients treated with MTX showed insignificantly better response than patients with CyA. CK levels in the MTX group decreased significantly after 1, 3, and 6 months, whereas a significant reduction in the CyA group was first observed after 6 months. IL-1Ra serum levels significantly dropped in the CyA group after two weeks, whereas in the MTX group the significant decrease was first seen after 3 months of treatment. Good correlation was found between each of the clinical parameters (MEFT, CA, and GPA), none of them showed any correlation with CK or IL-1Ra levels. CONCLUSIONS: Administration of MTX or CyA added to corticosteroids was associated with clinical and laboratory improvement. Changes in CK and IL-1Ra levels were not associated with parameters of clinical disease severity measured in this study.

Heterogenous nuclear RNP C1 and C2 core proteins are targets for an autoantibody found in the serum of a patient with systemic sclerosis and psoriatic arthritis.

OBJECTIVE: To determine a target recognized by anti-Bh autoantibody, found in the serum of a patient with the unusual coexistence of systemic sclerosis (SSc) and psoriatic arthritis (PsA). METHODS: Antigens recognized by the anti-Bh serum were characterized by indirect immunofluorescence on HeLa cells, by conventional immunoblotting using nuclear extract or partially purified preparation of heterogenous nuclear RNP (hnRNP) proteins, and by 2-dimensional immunoblotting. For the analysis of cross-reactivity and immunofluorescence patterns, autoantibodies were affinity-purified by blot elution and then retested. RESULTS: Comparison of the reactivity of the anti-Bh antibody with the monoclonal antibody 4F4 against both the hnRNP C proteins, together with the determination of biochemical properties of the autoantigens, led to the identification of C1 and C2 core proteins as the targets for the anti-Bh autoantibody. CONCLUSION: Several essential components of the spliceosome are targeted by autoantibodies that are present in the sera of patients with systemic rheumatic diseases. We also found that the hnRNP core proteins C1 and C2 are recognized by the autoantibody present in the serum of a patient with SSc and PsA. C1 and C2 hnRNP proteins should be added to the several intracellular autoantigens recently shown to be cleaved by interleukin-1beta-converting enzyme-like enzymes during apoptosis.