Differential responsiveness to immunoablative therapy in refractory rheumatoid arthritis is associated with level and avidity of anti-cyclic citrullinated protein autoantibodies: a case study

In order to identify pathogenic correlates of refractory rheumatoid arthritis (RA), antibodies against anti-cyclic citrullinated protein (ACPAs) were investigated in RA patients in whom the dysregulated immune system had been ablated by high-dose chemotherapy (HDC) and autologous haematopoietic stem cell transplantation (HSCT). Six patients with refractory RA were extensively characterized in terms of levels of total immunoglobulins, RA-specific autoantibodies (ACPAs and rheumatoid factor) and antibodies against rubella, tetanus toxoid (TT) and phosphorylcholine before and after HDC plus HSCT. Additionally, the avidity of ACPAs was measured before and after treatment and compared with the avidity of TT antibodies following repeated immunizations. Synovial biopsies were obtained by arthroscopy before HDC plus HSCT, and analyzed by immunohistochemistry. In the three patients with clinically long-lasting responses to HDC plus HSCT (median 423 days), significant reductions in ACPA-IgG levels after therapy were observed (median level dropped from 215 to 34 arbitrary units/ml; P = 0.05). In contrast, stable ACPA-IgG levels were observed in three patients who relapsed shortly after HDC plus HSCT (median of 67 days). Clinical responders had ACPA-IgG of lower avidity (r = 0.75; P = 0.08) and higher degree of inflammation histologically (r = 0.73; P = 0.09). Relapse (after 38 to 530 days) in all patients was preceded by rising levels of low avidity ACPA-IgG (after 30 to 388 days), in contrast to the stable titres of high avidity TT antibodies. In conclusion, humoral autoimmune responses were differentially modulated by immunoablative therapy in patients with synovial inflammation and low avidity ACPA-IgG autoantibodies as compared with patients with high levels of high avidity ACPA-IgG. The distinct clinical disease course after immunoablative therapy based on levels and avidity of ACPA-IgG indicates that refractory RA is not a single disease entity

Antibodies to citrullinated proteins and differences in clinical progression of rheumatoid arthritis

Antibodies to citrullinated proteins (anti-cyclic-citrullinated peptide [anti-CCP] antibodies) are highly specific for rheumatoid arthritis (RA) and precede the onset of disease symptoms, indicating a pathogenetic role for these antibodies in RA. We recently showed that distinct genetic risk factors are associated with either anti-CCP-positive disease or anti-CCP-negative disease. These data are important as they indicate that distinct pathogenic mechanisms are underlying anti-CCP-positive disease or anti-CCP-negative disease. Likewise, these observations raise the question of whether anti-CCP-positive RA and anti-CCP-negative RA are clinically different disease entities. We therefore investigated whether RA patients with anti-CCP antibodies have a different clinical presentation and disease course compared with patients without these autoantibodies. In a cohort of 454 incident patients with RA, 228 patients were anti-CCP-positive and 226 patients were anti-CCP-negative. The early symptoms, tender and swollen joint count, and C-reactive protein level at inclusion, as well as the swollen joint count and radiological destruction during 4 years of follow-up, were compared for the two groups. There were no differences in morning stiffness, type, location and distribution of early symptoms, patients' rated disease activity and C-reactive protein at inclusion between RA patients with and without anti-CCP antibodies. The mean tender and swollen joint count for the different joints at inclusion was similar. At follow-up, patients with anti-CCP antibodies had more swollen joints and more severe radiological destruction. Nevertheless, the distribution of affected joints, for swelling, bone erosions and joint space narrowing, was similar. In conclusion, the phenotype of RA patients with or without anti-CCP antibodies is similar with respect to clinical presentation but differs with respect to disease course

The Stop Arthritis Very Early (SAVE) trial, an international multicentre, randomised, double-blind, placebo-controlled trial on glucocorticoids in very early arthritis

Glucocorticoids (GCs) are often used as early arthritis treatment and it has been suggested that they induce remission or at least delay the development of rheumatoid arthritis (RA) and the need to start disease-modifying antirheumatic drugs (DMARDs). To test the effect of GCs on patients with very early arthritis (symptom duration of <16 weeks) in a randomised controlled trial. Patients received a single intramuscular injection of 120 mg methylprednisolone or placebo (PL) and were followed up for 52 weeks. Primary end point was drug-free clinical remission, both at weeks 12 and 52. Among secondary outcomes were fulfillment of remission criteria at weeks 2, 12 or 52, time course of 'core set variables' and proportion of patients starting DMARDs. 17.0% of all analysed subjects (65/383) achieved persistent remission: 17.8% (33/185) of the PL group, 16.2% (32/198) of the patients receiving methylprednisolone (OR=1.13, 95% CI 0.66 to 1.92, p=0.6847). Analyses of secondary end points showed significant clinical benefits of the GC only at week 2. These differences subsequently disappeared. DMARDs were started in 162 patients: 50.3% methylprednisolone and 56.7% PL patients had to start DMARD treatment (OR=0.78, 95% CI 0.49 to 1.22, p=0.30). Significantly more patients with polyarthritis than with oligoarthritis received DMARDs (OR=2.84, 95% CI 1.75 to 4.60, p <0.0001). Neither remission nor development of RA is delayed by GC treatment. Remission is rare in the first year of very early arthritis, occurring in <20% of the patients. Also, the need to start DMARDs was not influenced by GC treatmen

Associations between synovial inflammation and circulating ACPA-IgG autoantibodies

<p><b>Copyright information:</b></p><p>Taken from "Differential responsiveness to immunoablative therapy in refractory rheumatoid arthritis is associated with level and avidity of anti-cyclic citrullinated protein autoantibodies: a case study"</p><p>http://arthritis-research.com/content/9/5/R106</p><p>Arthritis Research & Therapy 2007;9(5):R106-R106.</p><p>Published online 10 Oct 2007</p><p>PMCID:PMC2212565.</p><p></p> Semiquantitative scores of individual patients before immunoablative therapy, scoring synovial infiltration for CD68 expression (macrophages), CD138 expression (plasma cells), CD20 expression, CD79a expression (B cells), CD3 expression (T-cells), Ki-67 expression (proliferation marker) and total inflammation. Correlation of synovial inflammation scores with serum levels of antibodies against anti-cyclic citrullinated protein (ACPA)-IgG (open symbols) and avidity of ACPA-IgG (closed symbols) before immunoablative treatment. Each symbol corresponds to a distinct patient. Correlation of serum levels of ACPA-IgG with C-reactive protein (CRP) levels (= 0.56, < 0.001) during complete follow up in the three patients whose ACPA-IgG levels are susceptible to immunoablative therapy ('ACPA responders'). Correlation of serum levels of ACPA-IgG with CRP levels (= 0.027, = 0.86) during complete follow up in the three patients whose ACPA-IgG levels remained stable after immunoablative therapy ('ACPA nonresponders'). AU, arbitrary units; NaSCN, sodium thiocyanate