Maintenance of antibody response to diphtheria/tetanus vaccine in patients aged 2-5 years with polyarticular-course juvenile idiopathic arthritis receiving subcutaneous abatacept

Background: Patients with polyarticular-course juvenile idiopathic arthritis (pJIA), receiving disease-modifying anti-rheumatic drugs with immunosuppressive effects, may be at increased risk of vaccine-preventable infections. This substudy assessed protective antibody responses to diphtheria and tetanus vaccination given prior to study enrolment in patients with pJIA. Findings: This was a substudy of a 24-month, single-arm, open-label, multicenter, Phase III trial (NCT01844518) of subcutaneous abatacept in children with active pJIA (N = 219). Patients aged 2-5 years, with 652 continuous months of weekly weight-tiered (10-< 25 kg [50 mg], 25-< 50 kg [87.5 mg]) subcutaneous abatacept treatment (with/without methotrexate and/or low-dose corticosteroids), who received diphtheria/tetanus vaccine prior to enrolment, were eligible. Protective antibody levels to diphtheria/tetanus (> 0.1 IU/mL), and safety, were assessed. Overall, 29 patients were analyzed: 19 (65.5%), 1 (3.4%) and 9 (31.0%) patients had > 12, 6-12 and 2-< 6 months of abatacept exposure, respectively. All patients had protective antibody levels to tetanus and 26 (89.7%) patients had protective antibody levels to diphtheria. Of the 3 patients without protective antibody levels to diphtheria, each had an antibody level of 0.1 IU/mL, bordering the lower threshold of protection. Concomitant use of methotrexate and/or low-dose corticosteroids had no evident effect on antibody levels. No unexpected adverse events, including cases of diphtheria or tetanus, were reported during the 24-month period. Conclusions: Patients aged 2-5 years with pJIA who received 2-24 months of weekly subcutaneous abatacept, with or without concomitant methotrexate and/or low-dose corticosteroids, maintained effective diphtheria and tetanus vaccination protection without new safety signals

Surface plasmon resonance fiber sensor for real-time and label-free monitoring of cellular behavior

This paper reports on the application of an optical fiber biosensor for real-time analysis of cellular behavior. Our findings illustrate that a fiber sensor fabricated from a traditional telecommunication fiber can be integrated into conventional cell culture equipment and used for real-time and label-free monitoring of cellular responses to chemical stimuli. The sensing mechanism used for the measurement of cellular responses is based on the excitation of surface plasmon resonance (SPR) on the surface of the optical fiber. In this proof of concept study, the sensor was utilized to investigate the influence of a number of different stimuli on cells-we tested the effects of trypsin, serum and sodium azide. These stimuli induced detachment of cells from the sensor surface, uptake of serum and inhibition of cellular metabolism, accordingly. The effects of different stimuli were confirmed with alamar blue assay, phase contrast and fluorescence microscopy. The results indicated that the fiber biosensor can be successfully utilized for real-time and label-free monitoring of cellular response in the first 30. min following the introduction of a stimulus. Furthermore, we demonstrated that the optical fiber biosensors can be easily regenerated for repeated use, proving this platform as a versatile and cost-effective sensing tool

Methotrexate withdrawal at 6 vs 12 months in juvenile idiopathic arthritis in remission a randomized clinical trial

Context Novel therapies have improved the remission rate in chronic inflammatory disorders including juvenile idiopathic arthritis (JIA). Therefore, strategies of tapering therapy and reliable parameters for detecting subclinical inflammation have now become challenging questions. Objectives To analyze whether longer methotrexate treatment during remission of JIA prevents flares after withdrawal of medication and whether specific biomarkers identify patients at risk for flares. Design, Setting, and Patients Prospective, open, multicenter, medicationwithdrawal randomized clinical trial including 364 patients (median age, 11.0 years) with JIA recruited in 61 centers from 29 countries between February 2005 and June 2006. Patients were included at first confirmation of clinical remission while continuing medication. At the time of therapy withdrawal, levels of the phagocyte activation marker myeloidrelated proteins 8 and 14 heterocomplex (MRP8/14) were determined. Intervention Patients were randomly assigned to continue with methotrexate therapy for either 6 months (group 1 [n=183]) or 12 months (group 2 [n=181]) after induction of disease remission. Main Outcome Measures Primary outcome was relapse rate in the 2 treatment groups; secondary outcome was time to relapse. In a prespecified cohort analysis, the prognostic accuracy of MRP8/14 concentrations for the risk of flares was assessed. Results Intention-to-treat analysis of the primary outcome revealed relapse within 24 months after the inclusion into the study in 98 of 183 patients (relapse rate, 56.7%) in group 1 and 94 of 181 (55.6%) in group 2. The odds ratio for group 1 vs group 2 was 1.02 (95% CI, 0.82-1.27; P=.86). The median relapse-free interval after inclusion was 21.0 months in group 1 and 23.0 months in group 2. The hazard ratio for group 1 vs group 2 was 1.07 (95% CI, 0.82-1.41; P=.61). Median follow-up duration after inclusion was 34.2 and 34.3 months in groups 1 and 2, respectively. Levels of MRP8/14 during remission were significantly higher in patients who subsequently developed flares (median, 715 [IQR, 320-1110] ng/mL) compared with patients maintaining stable remission (400 [IQR, 220-800] ng/mL; P=.003). Low MRP8/14 levels indicated a low risk of flares within the next 3 months following the biomarker test (area under the receiver operating characteristic curve, 0.76; 95% CI, 0.62-0.90). Conclusions In patients with JIA in remission, a 12-month vs 6-month withdrawal of methotrexate did not reduce the relapse rate. Higher MRP8/14 concentrations were associated with risk of relapse after discontinuing methotrexate. Trial Registration isrctn.org Identifier: ISRCTN18186313.publishersversionPeer reviewe

The effect of infliximab plus methotrexate on the modulation of inflammatory disease markers in juvenile idiopathic arthritis: analyses from a randomized, placebo-controlled trial

Peer reviewe

The role of pulmonary arterial stiffness in COPD

AbstractCOPD is the second most common cause of pulmonary hypertension, and is a common complication of severe COPD with significant implications for both quality of life and mortality. However, the use of a rigid diagnostic threshold of a mean pulmonary arterial pressure (mPAP) of ≥25mHg when considering the impact of the pulmonary vasculature on symptoms and disease is misleading. Even minimal exertion causes oxygen desaturation and elevations in mPAP, with right ventricular hypertrophy and dilatation present in patients with mild to moderate COPD with pressures below the threshold for diagnosis of pulmonary hypertension. This has significant implications, with right ventricular dysfunction associated with poorer exercise capability and increased mortality independent of pulmonary function tests.The compliance of the pulmonary artery (PA) is a key component in decoupling the right ventricle from the pulmonary bed, allowing the right ventricle to work at maximum efficiency and protecting the microcirculation from large pressure gradients. PA stiffness increases with the severity of COPD, and correlates well with the presence of exercise induced pulmonary hypertension. A curvilinear relationship exists between PA distensibility and mPAP and pulmonary vascular resistance (PVR) with marked loss of distensibility before a rapid rise in mPAP and PVR occurs with resultant right ventricular failure. This combination of features suggests PA stiffness as a promising biomarker for early detection of pulmonary vascular disease, and to play a role in right ventricular failure in COPD. Early detection would open this up as a potential therapeutic target before end stage arterial remodelling occurs