Glucocorticoids suppress T cell function by up-regulating microRNA-98.

OBJECTIVE: To identify microRNAs (miRNAs) in human T cells that can explain known antiinflammatory properties of steroids. METHODS: Activated human CD4+ T cells from healthy donors were exposed to 1 µM methylprednisolone (MP) in vitro and then subjected to miRNA and messenger RNA microarray analyses. Changes in expression profiles were recorded. Using quantitative polymerase chain reaction (qPCR), flow cytometry, and enzyme-linked immunosorbent assay (ELISA), we confirmed the suppression of predicted targets, and through miRNA transfection experiments, we could suggest mechanistic links. RESULTS: We identified numerous steroid-responsive genes and miRNAs-many known and some novel-including multiple previously unknown proinflammatory genes suppressed by MP. Further studies using qPCR, flow cytometry, and ELISA demonstrated that methylprednisolone increased the expression of miRNA-98 (miR-98) and suppressed the levels of predicted targets, including interleukin-13 and 3 tumor necrosis factor receptors (TNFRs): Fas, FasL, and TNFR superfamily member 1B. Forced expression of miR-98 in T cells resulted in suppression of the same targets. CONCLUSION: The findings of this study demonstrate a link between miR-98 expression and the effects of MP and provide evidence suggesting that MP acts through miR-98 to inhibit specific proinflammatory targets. Identification of this antiinflammatory mechanism of glucocorticoids is important, since it may pave the way toward the elusive goal of dissociating adverse effects from therapeutic effects.

Evaluation of the association between Hispanic ethnicity and disease activity and severity in a large cohort of patients with juvenile idiopathic arthritis.

To examine the association between ethnicity and disease activity in patients with juvenile idiopathic arthritis (JIA), and to determine the association of ethnicity with disease severity and disability in this population. CARRAnet, a US database containing information (collected between May 2010 and June 2011) on almost 3,000 subjects with JIA, was used. Demographic variables were compared between Hispanic patients and non-Hispanic patients. Mann-Whitney and chi-square tests were used to compare indicators of disease activity, as well as imaging evidence of joint damage, and Childhood Health Assessment Questionnaire (CHAQ) scores between ethnicities. Two linear regression models were used to determine the association of ethnicity with number of active joints in JIA, and the association between ethnicity and disability (CHAQ scores). A total of 2,704 patients with JIA (277 Hispanic; 2,427 non-Hispanic) were included. Income and health insurance coverage were higher in non-Hispanics. RF-positive polyarticular JIA, positive RF and anti-CCP, as well as use of systemic steroids were more frequent in Hispanics. Imaging evidence of joint damage was present in 32 % of the Hispanic patients compared to 24 % of the non-Hispanic patients (p = 0.008). In multivariate linear regression analyses, the number of active joints was significantly higher in Hispanics than in non-Hispanics (p = 0.03), as well as CHAQ scores (p = 0.003), after adjusting for confounders. Hispanic patients with JIA had higher disease activity than non-Hispanic patients, as well as higher disease severity and disability. Since ethnicity influences disease activity, severity, and disability, different management and treatment plans should be planned accordingly.

Disease-modifying antirheumatic drug use in the treatment of juvenile idiopathic arthritis: a cross-sectional analysis of the CARRA Registry.

OBJECTIVE: To characterize disease-modifying antirheumatic drug (DMARD) use for children with juvenile idiopathic arthritis (JIA) in the United States and to determine patient factors associated with medication use. METHODS: We analyzed cross-sectional baseline enrollment data from the Childhood Arthritis and Rheumatology Research Alliance (CARRA) Registry from May 2010 through May 2011 for children with JIA. Current and prior medication use was included. We used parsimonious backward stepwise logistic regression models to calculate OR to estimate associations between clinical patient factors and medication use. RESULTS: We identified 2748 children with JIA with a median disease duration of 3.9 years from 51 US clinical sites. Overall, 2023 (74%) had ever received a nonbiologic DMARD and 1246 (45%) had ever received a biologic DMARD. Among children without systemic arthritis, methotrexate use was most strongly associated with uveitis (OR 5.2, 95% CI 3.6-7.6), anticitrullinated protein antibodies (OR 4.5, 95% CI 1.7-12), and extended oligoarthritis (OR 4.1, 95% CI 2.5-6.6). Among children without systemic arthritis, biologic DMARD use was most strongly associated with rheumatoid factor (RF)-positive polyarthritis (OR 4.3, 95% CI 2.9-6.6), psoriatic arthritis (PsA; OR 3.0, 95% CI 2.0-4.4), and uveitis (OR 2.8, 95% CI 2.1-3.7). Among children with systemic arthritis, 160 (65%) ever received a biologic DMARD; tumor necrosis factor inhibitor use was associated with polyarthritis (OR 2.5, 95% CI 3.8-16), while interleukin 1 inhibitor use was not. CONCLUSION: About three-quarters of all children with JIA in the CARRA Registry received nonbiologic DMARD. Nearly one-half received biologic DMARD, and their use was strongly associated with RF-positive polyarthritis, PsA, uveitis, and systemic arthritis.