Clonal expansions in selected TCR BV families of rheumatoid arthritis patients are reduced by treatment with the TNFα inhibitors etanercept and infliximab.

Clonal expansions of autoreactive CD4+ T cells are frequently present in patients with rheumatoid arthritis (RA) and are stable over long periods of time. This study was undertaken to investigate the influence of anti-TNFα treatment on such clonal expansions in the peripheral CD4+ T-cell compartment. TNFα inhibiting therapies significantly reduced the total number of expanded clonotypes. This effect was mainly observed in clonal expansions in the BV6 family, while in clonal expansions of the BV14 family no such effect was seen. No change in the percentage of CD4+ CD28 null T cells was observed. Serum concentrations of the pro-homeostatic cytokine IL-7 were found to increase in patients responding TNFα-inhibiting therapy. These data argue for a normalization of adaptive immune mechanisms under TNFα inhibiting therapies, which may be secondary to the control of inflammation but contribute to the efficacy of cytokine blockade therapy.

Negative association of the chemokine receptor CCR5 d32 polymorphism with systemic inflammatory response, extra-articular symptoms and joint erosion in rheumatoid arthritis.

INTRODUCTION: Chemokines and their receptors control immune cell migration during infections as well as in autoimmune responses. A 32 bp deletion in the gene of the chemokine receptor CCR5 confers protection against HIV infection, but has also been reported to decrease susceptibility to rheumatoid arthritis (RA). The influence of this deletion variant on the clinical course of this autoimmune disease was investigated. METHODS: Genotyping for CCR5d32 was performed by PCR and subsequent electrophoretic fragment length determination. For the clinical analysis, the following extra-articular manifestations of RA were documented by the rheumatologist following the patient: presence of rheumatoid nodules, major organ vasculitis, pulmonary fibrosis, serositis or a Raynaud's syndrome. All documented CRP levels were analyzed retrospectively, and the last available hand and feet radiographs were analyzed with regards to the presence or absence of erosive disease. RESULTS: Analysis of the CCR5 polymorphism in 503 RA patients and in 459 age-matched healthy controls revealed a significantly decreased disease susceptibility for carriers of the CCR5d32 deletion (Odds ratio 0.67, P = 0.0437). Within the RA patient cohort, CCR5d32 was significantly less frequent in patients with extra-articular manifestations compared with those with limited, articular disease (13.2% versus 22.8%, P = 0.0374). In addition, the deletion was associated with significantly lower average CRP levels over time (median 8.85 vs. median 14.1, P = 0.0041) and had a protective effect against the development of erosive disease (OR = 0.40, P = 0.0047). Intriguingly, homozygosity for the RA associated DNASE2 -1066 G allele had an additive effect on the disease susceptibility conferred by the wt allele of CCR5 (OR = 2.24, P = 0.0051 for carrier of both RA associated alleles) CONCLUSIONS: The presence of CCR5d32 significantly influenced disease susceptibility to and clinical course of RA in a German study population. The protective effect of this deletion, which has been described to lead to a decreased receptor expression in heterozygous patients, underlines the importance of chemokines in the pathogenesis of RA.

Low-dose prednisolone in rheumatoid arthritis: adverse effects of various disease modifying antirheumatic drugs.

OBJECTIVE: To assess the incidence and severity of disease modifying antirheumatic drug (DMARD)-induced adverse effects (AE) in patients with rheumatoid arthritis (RA) taking/not taking glucocorticoids (GC). More specifically, we tested whether GC can prolong the survival time of DMARD in patients receiving combination therapy. METHODS: In a retrospective study of 154 patients with RA, data were examined for DMARD therapy and duration of low-dose GC ((3/4) 7.5 mg prednisone equivalent/day). Patients were followed for 2-62 months, and AE were graded following WHO criteria. RESULTS: GC therapy significantly increased the duration of therapy with sulfasalazine (SSZ) from 10.4 +/- 2.3 to 22.5 +/- 1.9 months and for methotrexate (MTX) from 21.8 +/- 2.9 to 43.3 +/- 2.7 months. Stratifying the withdrawal of DMARD for occurrence of AE and loss of efficacy revealed that GC comedication significantly increased the time until AE for users of MTX (3.0 +/- 0.6 vs 18.8 +/- 1.3 mo; p < 0.05), hydroxychloroquine (HCQ; 34.5 +/- 4.6 vs 54.4 +/- 5.1 mo; p < 0.05), and gold (6.6 +/- 0.9 vs 10.5 +/- 0.9 mo; p < 0.05). In patients taking SSZ the time until cessation due to loss of efficacy increased significantly under GC comedication (16.8 +/- 1.2 vs 31.3 +/- 2.9 mo; p < 0.05). However, in patients taking azathioprine (AZA) the duration of therapy decreased from 44.4 +/- 2.6 to 22.3 +/- 1.6 months under GC due to both time until AE and loss of efficacy. Patients under comedication of MTX + GC, HCQ + GC, and AZA + GC experienced significantly more AE compared to the respective DMARD monotherapy. A highly significant reduction was observed in the frequency of erosive RA in patients with GC comedication (n = 30; 49.1%) compared to patients without low-dose GC (n = 81, 80.4%; OR 4.05, 95% CI 1.91-8.66, p < 0.0001). CONCLUSION: Low-dose GC retard radiological progression of RA and exhibit a differential effect on survival of DMARD and degree of AE due to DMARD. Further studies are warranted to address safety and interactions of chronic low-dose GC in RA patients treated with DMARD.

Association of PTPN22 1858 single-nucleotide polymorphism with rheumatoid arthritis in a German cohort: higher frequency of the risk allele in male compared to female patients.

The functional single-nucleotide polymorphism (SNP) of the gene PTPN22 is a susceptibility locus for rheumatoid arthritis (RA). The study presented here describes the association of the PTPN22 1858T allele with RA in a German patient cohort; 390 patients with RA and 349 controls were enrolled in the study. For 123 patients, clinical and radiographic documentation over 6 years was available from the onset of disease. Genotyping of the PTPN22 1858 SNP was performed using an restriction fragment length polymorphism PCR-based genotyping assay. The odds ratio to develop RA was 2.57 for carriers of the PTPN22 1858T allele (95% confidence interval (CI) 1.85-3.58, p < 0.001), and 5.58 for homozygotes (95% CI 1.85-16.79). The PTPN22 1858T allele was significantly associated not only with rheumatoid factor (RF) and anti-cyclic citrullinated peptide (CCP) positive RA, but also with RF and anti-CCP negative disease. The frequency of the PTPN22 1858T allele was increased disproportionately in male patients (53.8% compared to 33.0% in female patients, p < 0.001), and the resulting odds ratio for male carriers was increased to 4.47 (95% CI 2.5-8.0, p < 0.001). Moreover, within the male patient population, the rare allele was significantly associated with the HLA-DRB1 shared epitope (p = 0.01). No significant differences in disease activity or Larsen scores were detected. The results provide further evidence that the PTPN22 1858T allele is associated with RA irrespective of autoantibody production. The increased frequency of the risk allele in male patients and its association with the shared epitope indicate that the genetic contribution to disease pathogenesis might be more prominent in men.

Clonally expanded CD4+CD28null T cells in rheumatoid arthritis use distinct combinations of T cell receptor BV and BJ elements.

Clonally expanded, autoreactive CD4(+)CD28(null) cells can be found in the peripheral blood of patients with rheumatoid arthritis and have been shown to be associated with severeextra-articular disease manifestations. We investigated the size of the CD4(+)CD28(null) compartment and the TCR beta chain repertoire of expanded CD4(+) clonotypes in 94 rheumatoid arthritis patients by complementarity-determining region 3 (CDR3) length analysis (spectratyping) in the BV6 and BV14 TCR families, with primers specific for three arbitrarily chosen beta chain joining elements (BJ1S2, BJ2S3 and BJ2S7). The spectratyping results showed a strong correlation of the size of the CD4(+)CD28(null) compartment with the detected number of BV14 clonotypes, whereas no association with BV6 oligoclonality was found. Only clones using the BV14-BJ1S2 and BV14-BJ2S3 combinations contributed to this correlation, however, whereas BV14-BJ2S7 clones did not. This preferential correlation implies a role for the TCR beta chain in stimulating clonal outgrowth and argues against the previously suggested superantigenic stimulation of in-vivo-expanded clones. Instead, since no evidence for shared antigen specificity could be detected, clonal expansion of T cells in rheumatoid arthritis might be influenced by the BJ elements because of changes in the flexibility of the protein backbone of the beta-chain.

B lymphocytopenia in rheumatoid arthritis is associated with the DRB1 shared epitope and increased acute phase response.

The influence of HLA DRB1 alleles on B-cell homeostasis was analyzed in 164 patients with rheumatoid arthritis (RA). The percentages of CD19+ B lymphocytes determined in the peripheral circulation of 94 retrospectively recruited RA patients followed a bimodal distribution. Two frequency peaks (B-cell(low) patients and B-cell(high) patients) were separated by the population median of a B-cell frequency of 8.5% of all lymphocytes. Human leucocyte antigen genotyping revealed that the B-cell(low) patients were more frequently positive for the RA-associated HLA DRB1 shared epitope (SE) than were B-cell(high) patients. Accordingly, SE-positive patients had lower CD19 percentages in the rank-sum analysis when compared with SE-negative patients, and were markedly B lymphocytopenic when compared with a healthy control group. To confirm the differential frequencies of CD19+ B cells, absolute numbers in peripheral blood were determined prospectively in a cohort of 70 RA patients with recent onset disease. SE-positive patients were found to have lower absolute numbers of circulating CD19+ B cells. B-cell counts below the mean of the study population were associated with higher acute phase response and with increased levels of rheumatoid factor IgA. No correlation between absolute numbers of circulating B cells and radiographic progression of joint destruction was seen. The influence of immunogenetic parameters on B-cell homeostasis in RA reported here has not been described previously. The clinical relevance of B lymphocytopenia in SE-positive RA will be further investigated in longitudinal studies.