IntroductionThe objective of this study was to investigate the effects of tumor necrosis factor (TNF)-α inhibitors on circulating T helper-type 17 (Th17) cells and Th17-related cytokines in patients with rheumatoid arthritis (RA).MethodsThe frequencies of circulating Th17 cells and serum levels of Th17-related cytokines were determined using flow cytometry analysis and ELISA, respectively, in 48 RA patients both before (baseline) and six months after anti-TNF-α therapy. Therapeutic response was evaluated using European League Against Rheumatism (EULAR) response criteria.ResultsSignificantly higher baseline frequencies of circulating Th17 cells and serum levels of interleukin (IL)-6, IL-17, IL-21, IL-23 and TNF-α were observed in active RA patients than in 12 healthy controls (all P < 0.001). After anti-TNF-α therapy, 36 patients (75%) were EULAR responders (20 good responders and 16 moderate responders) and 12 (25.0%) were non-responders. The mean levels of circulating Th17 cells and IL-17 significantly decreased (1.13% vs. 0.79%; 43.1 pg/ml vs. 27.8 pg/ml; respectively, both P < 0.001) in parallel with clinical remission in responders. Levels of IL-6, IL-21, IL-23 and TNF-α were significantly decreased after anti-TNF-α therapy in responders. In contrast, the mean levels of circulating Th17 cells and IL-17 significantly increased after anti-TNF-α therapy (2.94% vs. 4.23%; 92.1 pg/ml vs. 148.6 pg/ml; respectively, both P < 0.05) in non-responders. Logistic regression analysis identified a high baseline level of IL-17 as a significant predictor of poor therapeutic response.ConclusionsThe beneficial effect of anti-TNF-α therapy might involve a decrease in Th17-related cytokines in responders, whereas rising levels of circulating Th17-cells and IL-17 were observed in patients with an inadequate response to anti-TNF-α therapy.

Objective. To investigate QuantiFERON-tuberculosis Gold (QFT-G) assay and tuberculin skin test (TST) for latent tuberculosis (TB) infection (LTBI) in patients with rheumatoid arthritis (RA) treated with adalimumab. Methods. We prospectively followed up 43 RA patients who received adalimumab therapy and underwent serial TSTs and QFT-G assays. TST was performed using Mantoux method and QFT-G assay was examined by measuring interferon-␥ levels in whole blood samples that were incubated with early secretary antigenic target-6 and culture filtrate protein 10.

Elevated frequencies of circulating Th17 cells and a positive correlation with disease activity in our AOSD patients suggest that Th17 cells contribute to the pathogenesis of this disease. Dysregulation of Th17 cells may be a common pathogenic mechanism that underlies the development of both AOSD and SLE.