Rheumatoid Arthritis: Ernestam S

Sundberg E, Grundtman C, Af Klint E, Lindberg J, Ernestam S, Ulfgren AK, Harris HE, Andersson U. · Department of Woman and Child Health, Pediatric Rheumatology Research Unit, Karolinska Institutet/Karolinska University Hospital, Stockholm, Sweden. · Arthritis Res Ther. · Pubmed #18346273 links to  free full text

Abstract: INTRODUCTION: High-mobility group box chromosomal protein 1 (HMGB1) has recently been identified as an endogenous mediator of arthritis. TNF and IL-1beta, pivotal cytokines in arthritis pathogenesis, both have the ability to induce the release of HMGB1 from myeloid and dendritic cells. It was, therefore, decided to investigate whether treatment based on TNF blockade in rheumatoid arthritis (RA) affects the expression of synovial HMGB1. METHODS: Repeated arthroscopy-guided sampling of synovial tissue was performed in nine patients with RA before and nine weeks after initiation of anti-TNF mAb (infliximab) therapy. Synovial biopsy specimens were analysed for HMGB1 protein by immunohistochemical staining and for HMGB1 mRNA expression by real-time reverse transcriptase PCR (RT-PCR). Statistical evaluations were based on Wilcoxon's signed rank tests or Spearman rank sum tests. RESULTS: Aberrant, extranuclear HMGB1 and constitutive nuclear HMGB1 expression, with histological signs of inflammation, were evident in all biopsies obtained before infliximab therapy. Signs of inflammation were still evident in the second biopsies obtained nine weeks after initiation of infliximab therapy. The cytoplasmic and extracellular expression of HMGB1 decreased in five patients, remained unchanged in one patient and increased in three patients, making the overall change in HMGB1 protein expression not significant. No correlation between the clinical response, as measured by disease activity score calculated for 28 joints (DAS28) or the American College of Rheumatology response criteria (ACR 20, 50, and 70), and the direction of change of HMGB1 expression in individual patients could be discerned. In addition, infliximab therapy did not alter HMGB1 mRNA synthesis. CONCLUSION: Pro-inflammatory HMGB1 expression during rheumatoid synovitis was not consistently influenced by TNF-blocking therapy with infliximab. This suggests that TNF is not the main inducer of extranuclear HMGB1 during synovitis and that HMGB1 may represent a TNF-independent molecule that could be considered as a possible target for future therapeutic intervention in RA.

Kastbom A, Bratt J, Ernestam S, Lampa J, Padyukov L, Söderkvist P, Skogh T. · Linköping University, Linköping, Sweden. · Arthritis Rheum. · Pubmed #17265480 links to  free full text

Abstract: OBJECTIVE: To determine whether a functional single-nucleotide polymorphism in the gene encoding Fcgamma receptor type IIIA (FcgammaRIIIA) correlates with the response to treatment with tumor necrosis factor alpha inhibitors in rheumatoid arthritis (RA). METHODS: The study population comprised 282 Swedish patients with RA in whom the therapeutic efficacy of conventional disease-modifying antirheumatic drugs had been insufficient. Infliximab or etanercept treatment was initiated, and patients were evaluated after 3 months, using the American College of Rheumatology 20% improvement criteria (ACR20), the ACR50, and the ACR70 or the European League Against Rheumatism (EULAR) criteria. The chi-square test was used to compare response rates across FcgammaRIIIA genotypes. RESULTS: No differences in genotype distribution were observed among nonresponders compared with ACR20 responders (P = 0.80), ACR50 responders (P = 0.56), or ACR70 responders (P = 0.91). Similar results were observed when analyzing infliximab and etanercept separately or when using the EULAR response criteria. CONCLUSION: Unlike the findings of a previous study, the results of the current study suggest that the 158V/F polymorphism of FcgammaRIIIA is very unlikely to influence the clinical efficacy of infliximab or etanercept in patients with RA.

Kopp S, Alstergren P, Ernestam S, Nordahl S, Morin P, Bratt J. · Department of Clinical Oral Physiology, Institute of Odontology, Karolinska Institutet, Department of Rheumatology, Huddinge, Sweden. · Cells Tissues Organs. · Pubmed #16088130 No free full text.

Abstract: The aims were to investigate the effect of intravenous infusions of the tumor necrosis factor-alpha (TNF-alpha) antibody infliximab on symptoms and signs of temporomandibular joint (TMJ) involvement in relation to effects on synovial fluid and plasma proinflammatory TNF-alpha, interleukin-1beta (IL-1beta) and interleukin-6 as well as antiinflam matory soluble TNF receptor II (TNF-sRII), interleukin-1 receptor antagonist (IL-1ra), soluble IL-1 receptor II (IL-1sRII) and interleukin-10 (IL-10) in patients with active rheumatoid arthritis (RA). Nineteen patients with TMJ involvement taking methotrexate were included in the study. TMJ and general joint pain intensity as well as pain on mandibular movements, tenderness to digital palpation, pressure pain threshold and maximum mouth-opening capacity were assessed in a clinical examination. The effect of infliximab was assessed after 2 and 14 or 22 weeks. TMJ synovial fluid and venous blood were collected for cytokine analysis at all occasions while determination of erythrocyte sedimentation rate and C-reactive protein were performed at baseline and at long-term follow-up only. Reduction of TMJ pain was associated with raised levels of synovial fluid TNF-sRII and IL-1sRII as well as raised plasma levels of IL-1ra and IL-10. Decreased erythrocyte sedimentation rate was associated with decreased tenderness to digital palpation. Reduced general joint pain intensity was associated with reduced plasma levels of IL-6 and C-reactive protein. In conclusion, systemic treatment with a combination of infliximab and methotrexate reduces TMJ pain in RA in association with an increase in anti-inflammatory cytokines and receptors in synovial fluid and plasma.

Ernestam S, Lampa J, Rogberg S, Rönnelid J, Klareskog L, Hafström I. · Department of Rheumatology, Huddinge University Hospital, Karolinska Institute, Stockholm, Sweden. · J Rheumatol. · Pubmed #12913930 No free full text.

Abstract: OBJECTIVE: Intramuscular gold is a well documented treatment in rheumatoid arthritis (RA), but its mechanism of action is still poorly understood. From an observation that gold sodium thiomalate (GSTM) induces monocyte-derived interleukin 6 (IL-6) and IL-10 production in vitro, a hypothesis has been proposed that gold exerts its action mainly as a selective immunostimulator rather than as a general immunosuppressant. In this prospective study we investigated cytokine production in peripheral blood from patients with RA during treatment with GSTM. METHODS: A total of 20 patients with RA were treated with GSTM for at least 3 months. Disease activity was recorded at baseline, 12, 20, and 28 weeks. The ELISPOT method was used to measure spontaneous production of IL-6, IL-10, and interferon-g (IFN-g) from peripheral blood mononuclear cells (PBMC) at baseline and 4 and 12 weeks and production after incubation with GSTM in vitro, at different concentrations (0, 3, 12.5, 40 micro g/ml) at baseline. IL-6 and IL-10 concentrations in serum were measured with ELISA. RESULTS: The numbers of IL-10-producing cells were increased after 4 weeks' treatment with GSTM (p < 0.01). The numbers of cells spontaneously producing IL-6 were increased after 4 weeks (p < 0.01) and 12 weeks (p < 0.01). The numbers of IFN-g-producing cells were increased after 4 weeks (p < 0.01). Serum concentrations of IL-10 were increased after 4 weeks (p < 0.01). Serum concentrations of IL-6 were not changed at any timepoint. The in vitro effect of GSTM on IL-10 production from PBMC at baseline predicted development of skin reactions during GSTM treatment, with lack of skin reactions being associated with high gold induced IL-10 production (p < 0.05). There was no correlation between clinical response and cytokine production. CONCLUSION: This study indicates an immunostimulatory effect of GSTM treatment in patients with RA. The increase in IL-10 production during GSTM treatment may contribute to the positive effects of gold in RA.

Catrina AI, Lampa J, Ernestam S, af Klint E, Bratt J, Klareskog L, Ulfgren AK. · Department of Rheumatology, Karolinska Hospital, Stockholm, Sweden. · Rheumatology (Oxford). · Pubmed #12011369 links to  free full text

Abstract: OBJECTIVES: Matrix metalloproteinases (MMPs) are cytokine-modulated enzymes that play an important role in the pathogenesis of rheumatoid arthritis (RA) by inducing bone resorption and cartilage destruction. This study evaluated the modulation of serum and synovial MMPs and their inhibitor, tissue inhibitor of matrix metalloproteinases (TIMP)-1, by therapy with soluble tumour necrosis factor (TNF) alpha receptor (etanercept). METHODS: Serum samples were collected from 60 RA patients at baseline and after 8 or 12 weeks of treatment. Paired synovial biopsies were obtained from 11 patients at two time points, before and after 8 weeks of treatment. We measured serum levels of MMP-1, MMP-3 and TIMP-1 by ELISA. Immunohistological analysis of synovial tissue was performed using monoclonal antibodies specific for MMP-1, MMP-3 and TIMP-1. RESULTS: Etanercept therapy significantly down-regulated serum levels of MMP-3 and MMP-1 in parallel with the reduction in inflammatory parameters (C-reactive protein concentration and erythrocyte sedimentation rate) in RA patients. Baseline pretreatment serum levels of MMP-3 correlated with changes in clinical disease activity during therapy. No consistent changes in serum level of TIMP-1 were observed, while ratios of MMP-1 and MMP-3 to TIMP-1 were down-regulated following etanercept treatment. Immunohistochemical analyses revealed great interindividual variability, with generally a high level of expression of MMP and low expression of TIMP. No significant change in the pattern or number of positive cells occurred during therapy. CONCLUSIONS: In RA patients, etanercept therapy down-regulates serum levels of MMP-3 and MMP-1 and the ratio between MMPs and TIMP-1. This may be an important mechanism for the prevention of future development of joint damage.

Augustsson J, Eksborg S, Ernestam S, Gullström E, van Vollenhoven R. · Department of Rheumatology, Karolinska University Hospital Solna, 171 76 Stockholm, Sweden. · Ann Rheum Dis. · Pubmed #17502359 No free full text.

Abstract: BACKGROUND AND OBJECTIVE: Treatment-limiting infusion reactions to infliximab have not been fully explained in rheumatoid arthritis patients. Our main objective is to investigate the role of daily oral glucocorticoids use on such reactions. METHOD: Forty-three patients with immediate-type infusion reactions were identified in a large registry-based cohort. These patients were then compared with the entire cohort (n = 639) and, in a separate analysis, to a nested matched control group (n = 43). The following base-line variables were compared: use of oral glucocorticoids, health-assessment questionnaire, 28-joint count-based disease activity score, duration of disease and number of failed disease-modifying antirheumatic drugs. RESULTS: The proportion of infusions associated with infusion reactions decreased significantly during the study period (p = 0.0024). Fifty per cent of the patients in the cohort were treated with daily low-dose glucocorticoids at baseline. 15/326 (4.6%) patients had an infusion reaction as compared with 28/324 (8.6%) of patients without glucocorticoid treatment (p = 0.057). In the matched comparison, 15/43 (35%) of the cases were on low-dose glucocorticoids as compared with 27/43 (64%) of the controls (p = 0.017). The use of low-dose glucocorticoids was associated with a significantly lower risk for a treatment-limiting infusion reactions in a Kaplan-Meier analysis (p = 0.04). The number needed to treat to prevent a treatment-limiting infusion reaction was 25 (95% CI: 13 to 527) in the cohort. CONCLUSION: The use of daily low-dose glucocorticoids is associated with a lower risk for treatment-limiting infusion reactions to infliximab. Overall, treatment-limiting infusion reactions have become significantly less common during the past 5 years.

Ernestam S, Hafström I, Werner S, Carlström K, Tengstrand B. · Department of Rheumatology, Division of Clinical Chemistry, Karolinska Institute at Karolinska University Hospital, Huddinge, Stockholm, Sweden. · J Rheumatol. · Pubmed #17477470 No free full text.

Abstract: OBJECTIVE: To determine if major reduction of inflammation with longterm tumor necrosis factor (TNF) antagonist treatment has any influence on the adrenal and gonadal axes in patients with rheumatoid arthritis (RA). METHODS: Forty-eight patients with RA were treated with infliximab or etanercept for 2 years. Disease activity, clinical response, and physical function were evaluated and serum levels of high sensitivity C-reactive protein and interleukin 6 were analyzed before start of treatment and after 1 and 2 years. At the same timepoints adrenocorticotropic hormone (ACTH), cortisol, and dehydroepiandrosterone sulfate (DHEAS) were analyzed; luteinizing hormone (LH), estradiol, and testosterone were analyzed as well in 18 male patients. RESULTS: DHEAS increased (p <or= 0.05) after 1 and 2 years of treatment with TNF antagonists. No change in serum levels of ACTH, cortisol, LH, estradiol, or testosterone was recorded during the 2 years. The increased levels of DHEAS correlated with improved physical function measured by Health Assessment Questionnaire (p <or= 0.01). There was no correlation between hormone levels and clinical response or inflammatory markers. A longitudinal stability in individual hormone levels was found between baseline and 2 years, most markedly for DHEAS levels (rs = 0.90, p <or= 0.01). A female subgroup characterized by low levels of DHEAS had a lower age at disease onset. CONCLUSION: The increased DHEAS levels may indicate an improved adrenal function during 2 years' treatment with TNF antagonists. Improved physical function, correlated to increased DHEAS levels, may be an effect of better adrenal function during powerful antiinflammatory treatment. The stability in individual hormone levels suggests a stable hormonal homeostasis, independent of inflammatory activity.

Kopp S, Alstergren P, Ernestam S, Nordahl S, Bratt J. · Department of Clinical Oral Physiology, Institute of Odontology, Karolinska Institutet, Huddinge, Sweden. · Scand J Rheumatol. · Pubmed #16766364 No free full text.

Abstract: OBJECTIVES: The aim of this study was to investigate the influence of plasma and synovial fluid tumour necrosis factor alpha (TNFalpha), interleukin-1beta (IL-1beta), IL-6, soluble TNF receptor II (TNF-sRII), IL-1 receptor antagonist (IL-1ra), soluble IL-1 receptor II (IL-1sRII) and IL-10 on the effect of the TNFalpha antibody infliximab on temporomandibular joint (TMJ) pain in patients with active rheumatoid arthritis (RA). METHODS: Fifteen patients with TMJ pain taking methotrexate were included in the study. The effect of intravenous infusions of infliximab was assessed after 14 or 22 weeks. TMJ resting and movement pain was assessed by a visual analogue scale (VAS) (0-100 mm) and samples of venous blood and TMJ synovial fluid were collected before and after treatment. RESULTS: The effect of infliximab on TMJ pain was influenced by pretreatment plasma levels of IL-1beta, IL-1ra, and IL-10 as well as pretreatment levels of TMJ synovial fluid IL-1sRII. High pretreatment levels of these cytokines and receptors as well as the presence of rheumatoid factor (RF) were associated with no or minor reduction in TMJ pain after treatment. CONCLUSIONS: Systemic treatment of RA with a combination of infliximab and methotrexate seems to be insufficient to alleviate TMJ pain in patients with RF or high pretreatment plasma levels of IL-1beta.

Ernestam S, af Klint E, Catrina AI, Sundberg E, Engström M, Klareskog L, Ulfgren AK. · Department of Rheumatology, Karolinska University Hospital, S-141 86 Stockholm, Sweden. · Arthritis Res Ther. · Pubmed #16507118 links to  free full text

Abstract: Blockade of tumour necrosis factor (TNF) is an effective treatment in rheumatoid arthritis (RA), but both non-responders and partial responders are quite frequent. This suggests that other pro-inflammatory cytokines may be of importance in the pathogenesis of RA and as possible targets for therapy. In this study we investigated the effect of TNF blockade (infliximab) on the synovial expression of IL-15 in RA in relation to different cell types and expression of other cytokines, to elucidate whether or not IL-15 is a possible target for therapy, independently of TNF blockade. Two arthroscopies with multiple biopsies were performed on nine patients with RA and knee-joint synovitis before and after three infusions of infliximab (3 mg/kg). Synovial biopsies were analysed with immunohistochemistry for expression of IL-15, TNF, IL-1alpha, IL-1ss and IFN-gamma, and for the cell surface markers CD3, CD68 and CD163. Stained synovial biopsy sections were evaluated by computerized image analysis. IL-15 expression was detected in all synovial biopsies taken at baseline. After infliximab therapy, the expression of IL-15 was increased in four patients and reduced in five. Synovial expression of IL-15 was not correlated with any CD marker or with the presence of any other cytokine. Synovial cellularity was decreased after 8 to 10 weeks of treatment with a significant reduction of the CD68-positive synovial cells, whereas no significant change was seen in the number of CD3-positive T cells and CD163-expressing macrophages. The number of TNF-producing cells in the synovial tissue at baseline was correlated with a good response to therapy. Thus, in this study the synovial expression of IL-15 in RA was not consistently influenced by TNF blockade, being apparently independent of TNF expression in the synovium. Consequently, we propose that IL-15 should remain as a therapeutic target in RA, regardless of the response to TNF blockade.

Tengstrand B, Ernestam S, Engvall IL, Rydvald Y, Hafström I. · Reumatologiska kliniken, Karolinska Universitetssjukhuset Huddinge, SE-141 86 Stockholm, Sweden. · Lakartidningen. · Pubmed #16408702 No free full text.

Abstract: TNF-blockade has been increasingly used in the treatment of rheumatoid arthritis (RA). However, the safety is unclear and an increased risk of both tuberculosis and other infections has been identified. Recently severe fibrosing alveolitis has also been reported in RA-patients treated with TNF-blockade. We report a further six RA patients, who during treatment with infliximab or etanercept developed fulminant lung fibrosis with alveolitis. For four of the patients, the fibrosing alveolitis was fatal. All patients were RF positive and above 60 years and five had mild fibrosis associated with RA before TNF-blockade treatment. Duration of TNF-blockade treatment was for three patients only two months and for the other three, 20-51 months. Age above 60 years and previous lung fibrosis appear to be risk factors for developing fibrosing alveolitis in RA patients treated with TNF-blockade.

Catrina AI, af Klint E, Ernestam S, Catrina SB, Makrygiannakis D, Botusan IR, Klareskog L, Ulfgren AK. · Rheumatology Research Laboratory, Karolinska University Hospital, Karolinska Institutet, S-17176 Stockholm, Sweden. · Arthritis Rheum. · Pubmed #16385498 links to  free full text

Abstract: OBJECTIVE: Treatment of rheumatoid arthritis (RA) with tumor necrosis factor (TNF)-blocking agents, including etanercept and infliximab, has resulted in reductions in the radiographic progression of RA. However, the exact mechanism by which this protection occurs has not been determined. In order to add to such knowledge, we investigated the effect of anti-TNF therapy on the expression of osteoprotegerin (OPG) and receptor activator of NF-kappaB ligand (RANKL) in synovial tissue. METHODS: The expression of OPG and RANKL in synovial biopsy specimens was evaluated by immunohistochemistry. Serial synovial biopsy specimens were obtained from 18 patients with RA, before and after treatment with etanercept (9 patients) or infliximab (9 patients). Biopsy specimens were evaluated by double-blind semiquantitative analysis and image analysis. The in vitro effect of TNF antagonists on the RANKL/OPG expression in osteoblasts and endothelial cells was evaluated by Western blotting. Statistical analysis was performed using Wilcoxon's signed rank test, followed by the Bonferroni correction for multiple comparisons of paired samples. The results of in vitro experiments were evaluated by one-way analysis of variance, with Tukey's post hoc test. RESULTS: Treatment with both infliximab and etanercept increased the expression of OPG in synovial tissue. After 8 weeks of treatment, neither infliximab nor etanercept influenced RANKL expression. In both groups of patients, the RANKL:OPG ratio decreased following therapy. In vitro, both of the TNF antagonists mimicked the in vivo effect, inducing a decrease in the RANKL:OPG ratio in TNF-primed osteoblasts and endothelial cells. CONCLUSION: Therapy with TNF antagonists in RA modulates the OPG/RANKL system, a potential mechanism that could explain the retardation of radiographic damage observed following anti-TNF therapy.

Wick MC, Ernestam S, Lindblad S, Bratt J, Klareskog L, van Vollenhoven RF. · Department of Rheumatology, Karolinska University Hospital, Solna, Sweden. · Scand J Rheumatol. · Pubmed #16234182 No free full text.

Abstract: OBJECTIVES: To determine whether the tumour necrosis factor-alpha (TNF-alpha) antagonist adalimumab (Humira) can be efficacious after secondary loss of efficacy (i.e. loss of clinical response in patients who had initially demonstrated clinical response) to infliximab (Remicade) or etanercept (Enbrel). PATIENTS AND METHODS: We studied 36 patients from the Stockholm TNF-alpha follow-up registry (STURE) who received adalimumab after secondary loss of efficacy to infliximab (group A, n = 27) or etanercept (group B, n = 9), and 26 patients who were started on adalimumab as the first TNF-alpha antagonist (group C). RESULTS: In group A, the baseline disease activity score 28 (DAS28) at infliximab institution was 5.5+/-0.2. During infliximab treatment, the mean best DAS28 was 3.7+/-0.2 (p<0.001), but increased to 5.2+/-0.3 when infliximab was stopped. After 3 months on adalimumab, the mean DAS28 decreased to 4.5+/-0.3 (p<0.003), and then to 4.2+/-0.2 at 6 months (p<0.001). In group B, the baseline DAS28 at etanercept institution was 6.6+/-0.5. During etanercept treatment, the mean best DAS28 was 4.6+/-0.5 (p<0.01), but increased to 5.7+/-0.4 by the time etanercept was stopped. After 3 months on adalimumab, the mean DAS28 decreased to 4.8+/-0.3 (p<0.005), and to 4.1+/-0.2 at 6 months (p<0.001). In group C, the mean baseline DAS28 was 5.6+/-0.3. After 6 months of adalimumab therapy, the DAS28 decreased to 3.5+/-0.4 (p<0.001). ACR20 responses with adalimumab in groups A, B, and C were similar (70-78%). CONCLUSIONS: For patients with secondary loss of efficacy from infliximab or etanercept, switching to adalimumab can restore a good clinical response.

van Vollenhoven RF, Ernestam S, Harju A, Bratt J, Klareskog L. · Department of Rheumatology, Karolinska Hospital, Stockholm, Sweden. · Arthritis Res Ther. · Pubmed #14680509 links to  free full text

Abstract: Etanercept can be used both as monotherapy and in combination with methotrexate (MTX), but direct comparisons of these two options have not yet been reported. In order to compare the results seen in actual practice between these two options, clinical data on 97 patients followed in the Stockholm TNFalpha Follow-Up Registry were analysed. In 57 of these patients etanercept was added to previously started MTX while the others were treated with etanercept alone. The two groups had similar levels of disease activity at baseline. After 3 months, a significantly lower mean disease activity score (28-joint count-based disease activity score) was attained by the patients on etanercept plus MTX. In this group, the number of patients achieving European League Against Rheumatism-defined remission was also significantly greater. Other disease outcomes showed non-significant trends in the same direction. These data suggest that the combination of etanercept plus MTX is clinically more efficacious than etanercept alone.

Padyukov L, Lampa J, Heimbürger M, Ernestam S, Cederholm T, Lundkvist I, Andersson P, Hermansson Y, Harju A, Klareskog L, Bratt J. · Unit of Rheumatology, Karolinska Hospital, Karolinska Institutet, Stockholm, Sweden. · Ann Rheum Dis. · Pubmed #12759288 links to  free full text

Abstract: BACKGROUND: Rheumatoid arthritis (RA) is a genetically complex disease where the response to different treatments varies greatly between different patients. This is the case with the tumour necrosis factor (TNF) blocking agents, where 20-40% of patients have been described as non-responders. No predictive markers exist as yet for the prognosis of response. OBJECTIVE: To analyse whether polymorphisms of several cytokine genes are associated with the responsiveness to TNF blockade with etanercept. METHODS: 123 patients with active RA were treated with etanercept and response rates were determined after three months using American College of Rheumatology (ACR)20 and disease activity score (DAS)28 response criteria. Genotyping was done for TNF (-308 TNFA), interleukin (IL)10 (-1087 IL10), transforming growth factor (TGF)beta1 (codon 25 TGFB1), and IL1 receptor antagonist (intron 2 IL1RN). RESULTS: 24 patients (20%) were defined as non-responders owing to their failure to fulfil any of the ACR20 or DAS28 response criteria. None of the recorded alleles was alone significantly associated with responsiveness to treatment. However, a certain combination of alleles (-308 TNF1/TNF1 and -1087 G/G) was associated with good responsiveness to etanercept (p<0.05). In addition, a combination of alleles influencing interleukin 1 receptor antagonist (IL1Ra) and TGFbeta1 production (A2 allele for IL1RN and rare C allele in codon 25 of TGFB1 gene) was associated with non-responsiveness (p<0.05). CONCLUSION: Genetic polymorphisms, which may influence the balance of pro- and anti-inflammatory cytokines of relevance for the course of RA, are associated with clinical responsiveness to etanercept treatment.