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ID PMID Title PublicationDate abstract
25847223 IL-6 blockade reverses the abnormal STAT activation of peripheral blood leukocytes from rh 2015 Jun Considering the interplay of multiple STATs in response to cytokines, we investigated how IL-6 and its blocking affect STAT signaling in rheumatoid arthritis (RA). Leukocytes obtained from RA patients before and after tocilizumab treatment and healthy donors (HDs) were cytokine-stimulated and STAT phosphorylation was analyzed by cytometry. RA patients had significantly fewer pSTAT1+, pSTAT3+, and pSTAT6+ monocytes and pSTAT5+ lymphocytes than HDs. After 24weeks of treatment, percentages of IFNγ-induced pSTAT1+ and IL-10-induced pSTAT3+ monocytes in RA patients increased, reaching levels comparable to HDs. pSTAT1+ and pSTAT3+ cells correlated inversely with RA disease activity index and levels of pSTAT+ cells at baseline were higher in patients with good EULAR response to tocilizumab. IFNγ-induced pSTAT1+ cells correlated inversely with memory T cells and anti-CCP levels. IL-10-induced pSTAT3+ cells correlated with Treg/Teff ratio. Our findings suggest that IL-6 blocking reduces the inflammatory mechanisms through the correction of STAT1 and STAT3 activation status.
27888222 Asymptomatic colitis induced by low-dose methotrexate. 2016 Nov 25 A woman aged 77 years with a history of rheumatoid arthritis (RA) presented with inflammatory colitis confined to her rectum, which was incidentally found by a screening colonoscopy. Histopathological examination of colonic biopsies showed non-specific inflammatory infiltrates of lymphocytes, the cause of which was unknown. She had been diagnosed with RA 5 years before, and she was receiving methotrexate 6 mg weekly, to which tocilizumab had been added 4 years earlier, which achieved stable control of her disease. She had no gastrointestinal symptoms or other health problems. Tocilizumab-induced colitis was considered likely, and the drug was discontinued. Metronidazole was also prescribed because of possible Clostridium difficile-associated colitis. 3 months later, a repeat colonoscopy showed no improvement of the colitis. The methotrexate was also discontinued, and folinic acid was prescribed daily for 2 weeks, leading to complete resolution of the colitis observed at repeat colonoscopy.
27863512 Rheumatoid synovial fibroblasts differentiate into distinct subsets in the presence of cyt 2016 Nov 18 BACKGROUND: We investigated two distinct synovial fibroblast populations that were located preferentially in the lining or sub-lining layers and defined by their expression of either podoplanin (PDPN) or CD248, and explored their ability to undergo self-assembly and transmigration in vivo. METHODS: Synovial fibroblasts (SF) were cultured in vitro and phenotypic changes following stimulation with interleukin (IL)-1β, tumor necrosis factor (TNF)-α, and transforming growth factor (TGF)-β1 were examined. To examine the phenotype of SF in vivo, a severe combined immunodeficiency (SCID) human-mouse model of cartilage destruction was utilised. RESULTS: SF in the lining layer in rheumatoid arthritis (RA) expressed high levels of PDPN compared to the normal synovium, whereas CD248 expression was restricted to sub-lining layer cells. TNF-α or IL1 stimulation in vitro resulted in an increased expression of PDPN. In contrast, stimulation with TGF-β1 induced CD248 expression. In the SCID human-mouse model, rheumatoid SF recapitulated the expression of PDPN and CD248. Fibroblasts adjacent to cartilage expressed PDPN, and attached to, invaded, and degraded cartilage. PDPN(+) CD248(-) SF preceded the appearance of PDPN(-) CD248(+) cells in contralateral implants. CONCLUSIONS: We have identified two distinct SF populations identified by expression of either PDPN or CD248 which are located within different anatomical compartments of the inflamed synovial membrane. These markers discriminate between SF subsets with distinct biological properties. As PDPN-expressing cells are associated with early fibroblast migration and cartilage erosion in vivo, we propose that PDPN-expressing cells may be an attractive therapeutic target in RA.
25369551 Altered profile of circulating microparticles in rheumatoid arthritis patients. 2015 Apr Microparticles (MPs) could be considered biomarkers of cell damage and activation as well as novel signalling structures. Since rheumatoid arthritis (RA) is characterized by immune and endothelial activation, the main aim of the present study was to analyse MP counts in RA patients. Citrated-blood samples were obtained from 114 RA patients, 33 healthy controls (HC) and 72 individuals with marked cardiovascular (CV) risk without autoimmune manifestations (CVR). MPs were analysed in platelet-poor plasma (PPP) and different subsets were identified by their surface markers: platelet- (CD41+), endothelial- (CD146+), granulocyte- (CD66+), monocyte- (CD14+) and Tang- (CD3+CD31+) derived. Disease activity score (DAS28), clinical and immunological parameters as well as traditional CV risk factors (diabetes, hypertension, dyslipidaemia and obesity) were registered from clinical records and all data were integrated using Principal Component Analysis (PCA). Absolute MP number was increased in RA patients compared with HC and positively correlated with traditional CV risk factors, similar to that of CVR subjects. In addition, frequency of the different MP subsets was different in RA patients and significantly associated with disease features. Moreover, in vitro assays revealed that MPs isolated from RA patients were able to promote endothelial activation and exhibited detrimental effects on human microvascular endothelial cells (HMEC-I) endothelial cell functionality. Circulating MPs from RA patients displayed quantitative and qualitative alterations that are the result of both disease-specific and traditional CV risk factors. Accordingly, this MP pool exhibited in vitro detrimental effects on endothelial cells, thus supporting their role as biomarkers of vascular damage.
25941817 Celastrol inhibits inflammatory stimuli-induced neutrophil extracellular trap formation. 2015 Neutrophil extracellular traps (NETs) are web-like structures released by activated neutrophils. Recent studies suggest that NETs play an active role in driving autoimmunity and tissue injury in diseases including rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). The purpose of this study was to investigate if celastrol, a triterpenoid compound, can inhibit NET formation induced by inflammatory stimuli associated with RA and SLE. We found that celastrol can completely inhibit neutrophil oxidative burst and NET formation induced by tumor necrosis factor alpha (TNFα) with an IC50 of 0.34 µM and by ovalbumin:anti-ovalbumin immune complexes (Ova IC) with an IC50 of 1.53 µM. Celastrol also completely inhibited neutrophil oxidative burst and NET formation induced by immunoglobulin G (IgG) purified from RA and SLE patient sera. Further investigating into the mechanisms, we found that celastrol treatment downregulated the activation of spleen tyrosine kinase (SYK) and the concomitant phosphorylation of mitogen-activated protein kinase kinase (MAPKK/MEK), extracellular-signal-regulated kinase (ERK), and NFκB inhibitor alpha (IκBα), as well as citrullination of histones. Our data reveals that celastrol potently inhibits neutrophil oxidative burst and NET formation induced by different inflammatory stimuli, possibly through downregulating the SYK-MEK-ERK-NFκB signaling cascade. These results suggest that celastrol may have therapeutic potentials for the treatment of inflammatory and autoimmune diseases involving neutrophils and NETs.
27143816 Increased Kappa/Lambda Hybrid Antibody in Serum Is a Novel Biomarker Related to Disease Ac 2016 The κ/λ hybrid antibodies in normal human serum were reported recently, but their clinical relevance has not yet been explored. Rheumatoid arthritis (RA) is one of the major joint diseases, and the early diagnosis and treatment of RA remain a challenge. Here, we developed a double-sandwich enzyme-linked immunosorbent assay system to quantify relative serum κ/λ hybrid antibody levels in RA patients, osteoarthritis (OA) patients, and healthy controls (HC) in order to assess their potential use as a serological biomarker of early disease and clinical activity and to preliminarily investigate their immunomodulatory roles in RA. Surprisingly, we found that κ/λ hybrid antibody was markedly increased in both early and established RA. Serum κ/λ hybrid antibody levels were significantly correlated with clinical indexes and inflammatory markers in RA. Further analysis showed a positive correlation between κ/λ hybrid antibody levels and the 28-joint disease activity score (DAS28). In conclusion, serum κ/λ hybrid antibodies in RA were identified for the first time. High levels of κ/λ hybrid antibody may be a useful tool in distinguishing early RA from OA and HC. We suggest κ/λ hybrid antibody as a marker for disease activity. The increased κ/λ hybrid antibodies were associated with inflammatory conditions in RA.
28012569 Efficacy of Methylprednisolone Acetate Versus Triamcinolone Acetonide Intra-articular Knee 2017 Jan PURPOSE: Triamcinolone hexacetonide (TH), triamcinolone acetonide (TA), and methylprednisolone acetate (MPA) are commonly used intra-articular steroid preparations. Studies suggest that intra-articular TH is more efficacious than MPA and TA in chronic inflammatory arthritis. However, it is unclear which of the latter two preparations has better efficacy. Thus, we compared intra-articular knee injections of MPA and TA in patients with chronic inflammatory arthritis. METHODS: This double-blind, randomized controlled trial included patients with rheumatoid arthritis or spondyloarthritis with an acutely swollen knee joint (≥1 week, <24 weeks). They were randomly assigned (1:1) to intra-articular knee injection with MPA or TA (80 mg, 2 mL of each). Evaluations were performed at 4, 12, and 24 weeks. Primary outcome was time to relapse (Kaplan-Meier) over 24 weeks, with relapse defined as return to baseline pain or swelling ≥1 week. Secondary outcomes were change in pain and swelling (using a numerical rating scale), range of movement, and occurrence of adverse effects. Primary analysis was intention to treat, with last observation carried forward. FINDINGS: One hundred patients (89 with rheumatoid arthritis) were randomly assigned in equal numbers to the MPA and TA groups. Nine patients relapsed in each group over 24 weeks. The mean time to relapse was not significantly different between the MPA and TA groups (20.8 [95% CI, 18.8-22.7] weeks and 20.9 [95% CI, 19.0-22.8] weeks, respectively; P = 0.9; hazard ratio = 1.0 [95% CI, 0.4-2.5]). In both groups, there was a significant decline in pain and swelling scores at all visits (P < 0.001); however, there were no significant intergroup differences. At 24 weeks, mean change in pain in the MPA (-4.4 [3.1]) and TA groups (-3.9 [2.8]) was not significantly different (P = 0.46). No infection, hematoma or hypopigmentation occurred in any patient. In addition, no significant intergroup differences were found in joint swelling, range of movement, modified (28 joint) Disease Activity Score using 3 variables, or Health Assessment Questionnaire over 24 weeks. IMPLICATIONS: No significant differences were found in efficacy between intra-articular knee injections with MPA and TA in these patients with chronic inflammatory arthritis. However, results need to be extrapolated cautiously because of the small sample size. Three-quarters of the patients remained relapse free at 24 weeks. Clinical Trials Registry of India (www.ctri.nic.in) identifier: CTRI/2015/09/006187.
24252003 Felty's syndrome and hypofibrinogenemia: an unusual target for anti-cyclic citrullinated p 2015 Sep BACKGROUND: Rheumatoid arthritis (RA) is a risk factor for the development of Felty's syndrome and large granular lymphocyte (LGL) leukemia. Anti-cyclic citrullinated peptide (CCP) antibodies are considered highly specific for RA and are directed against various citrullinated antigens, including citrullinated fibrinogen. Anti-CCP antibodies may interfere with the detection of citrullinated proteins and their function. In this article, we describe the possible inhibition of fibrinogen by anti-CCP antibodies with clinical consequences which have never been reported in the literature to our best knowledge. CASE REPORT: We present the case of a 79-year-old Caucasian woman with a longstanding history of untreated seropositive RA and who had been investigated for severe neutropenia since several months. The association of splenomegaly led to suspicion of Felty's syndrome. Flux cytometry was compatible with T-cell LGL leukemia. In addition, severe hypofibrinogenemia was detected. The later finding has not been consistently associated with the former clinical entities. Further investigations demonstrated that the anti-CCP antibodies of the patient also recognized the P41 peptide of citrullinated fibrinogen. The patient deceased of intracranial hemorrhage. CONCLUSION: It is likely, yet not definite, that high anti-citrullinated fibrinogen titers may contribute to low fibrinogen levels and could have contributed to the fatal hemorrhagic event.
26530039 Effects of tofacitinib monotherapy on patient-reported outcomes in a randomized phase 3 st 2015 Nov 4 INTRODUCTION: Tofacitinib is an oral Janus kinase inhibitor for the treatment of rheumatoid arthritis. METHOD: In this 6-month, phase 3, randomized, placebo-controlled trial, 611 patients with inadequate response to disease-modifying anti-rheumatic drugs (DMARD-IR) were randomized 4:4:1:1 to receive: tofacitinib 5 mg BID or tofacitinib 10 mg BID for the duration of the study, or placebo for 3 months followed by tofacitinib 5 mg BID or tofacitinib 10 mg BID. Patient-reported outcomes (PROs) included: Patient Global Assessment of Disease Activity (PtGA); Patient Assessment of Pain (Pain); Health Assessment Questionnaire-Disability Index (HAQ-DI); Medical Outcomes Survey (MOS) Short Form-36 (SF-36); Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-F); and MOS Sleep Scale. Time-to-event data (PtGA and Pain) were collected using an interactive voice response system daily diary (baseline through day 14). RESULTS: At month 3, tofacitinib 5 and 10 mg BID demonstrated statistically significant improvements versus placebo in PtGA (both p < 0.0001), Pain (both p < 0.0001), HAQ-DI (both p < 0.0001), SF-36 Physical (p < 0.0001) and Mental (p < 0.05 [5 mg BID] and p < 0.0001 [10 mg BID]), Component Summary scores and all domain scores (p < 0.05-p < 0.0001) and FACIT-F (both p < 0.0001). Statistically significant changes from baseline in MOS Sleep Scale were reported for 10 mg BID (p < 0.05). Benefits of tofacitinib treatment were rapid in onset and significant improvements were reported at week 2 for PtGA, Pain and HAQ-DI, and differentiation from baseline was seen as early as 3 days after treatment initiation for interactive voice response system (IVRS) PtGA and IVRS Pain. The numbers needed to treat for patients to report changes greater than or equal to the minimum clinically important difference in PtGA, Pain, HAQ-DI, SF-36 Physical Component Summary score and FACIT-F ranged between 4.0-6.1 (5 mg BID) and 3.2-5.0 (10 mg BID). CONCLUSION: Tofacitinib monotherapy in DMARD-IR patients resulted in statistically significant and clinically meaningful improvements in multiple PROs versus placebo at month 3, with sustained improvements over 6 months. TRIAL REGISTRATION: Clinicaltrials.gov registration NCT00814307 , registered 22 December 2008.
25231203 Developing the Polish Educational Needs Assessment Tool (Pol-ENAT) in rheumatoid arthritis 2015 Mar OBJECTIVES: To undertake cross-cultural adaptation and validation of the educational needs assessment tool (ENAT) for use with people with rheumatoid arthritis (RA) and systemic sclerosis (SSc) in Poland. METHODS: The study involved two main phases: (1) cross-cultural adaptation of the ENAT from English into Polish and (2) Cross-cultural validation of Polish Educational Needs Assessment Tool (Pol-ENAT). The first phase followed an established process of cross-cultural adaptation of self-report measures. The second phase involved completion of the Pol-ENAT by patients and subjecting the data to Rasch analysis to assess the construct validity, unidimensionality, internal consistency and cross-cultural invariance. RESULTS: An adequate conceptual equivalence was achieved following the adaptation process. The dataset for validation comprised a total of 278 patients, 237 (85.3 %) of which were female. In each disease group (145, RA and 133, SSc), the 7 domains of the Pol-ENAT were found to fit the Rasch model, X (2)(df) = 16.953(14), p = 0.259 and 8.132(14), p = 0.882 for RA and SSc, respectively. Internal consistency of the Pol-ENAT was high (patient separation index = 0.85 and 0.89 for SSc and RA, respectively), and unidimensionality was confirmed. Cross-cultural differential item functioning (DIF) was detected in some subscales, and DIF-adjusted conversion tables were calibrated to enable cross-cultural comparison of data between Poland and the UK. CONCLUSION: Using a standard process in cross-cultural adaptation, conceptual equivalence was achieved between the original (UK) ENAT and the adapted Pol-ENAT. Fit to the Rasch model, confirmed that the construct validity, unidimensionality and internal consistency of the ENAT have been preserved.
27849414 Clinical Features and Complications of Scleritis in Chinese Patients. 2018 PURPOSE: To characterize the clinical features of scleritis in Chinese patients. METHODS: The history, demographics, ocular findings, auxiliary examination findings, complications, systemic diseases and therapeutic effects were analyzed retrospectively. RESULTS: The study included 124 male and 169 female patients with scleritis. Anterior and posterior scleritis were, respectively, found in 243 and 42 patients. The other eight patients had both anterior and posterior involvement. The mean age of scleritis onset was 39.4 years. Systemic diseases associated with scleritis mainly included rheumatoid arthritis (RA) (4.4%), ankylosing spondylitis (AS) (3.4%), and tuberculosis (1.7%). Anterior uveitis (23.7%), complicated cataract (16.7%), and intraocular hypertension (12.6%) were common complications of scleritis. Scleritis was controlled in 94.6% of the patients treated with corticosteroids combined with immunosuppressive agents. CONCLUSIONS: Diffuse anterior scleritis was the most common scleritis entity in China. RA and AS were relatively common diseases associated with scleritis. Corticosteroids combined with immunosuppressive agents effectively controlled the disease.
25726511 ACTH: The forgotten therapy. 2015 May Although anti-inflammatory drugs are among the most common class of marketed drugs, chronic inflammatory conditions such as rheumatoid arthritis, multiple sclerosis or inflammatory bowel disease still represent unmet needs. New first-in-class drugs might be discovered in the future but the repurpose and further development of old drugs also offers promise for these conditions. This is the case of the melanocortin adrenocorticotropin hormone, ACTH, used in patients since 1952 but regarded as the last therapeutic option when other medications, such as glucocorticoids, cannot be used. Better understanding on its physiological and pharmacological mechanisms of actions and new insights on melanocortin receptors biology have revived the interest on rescuing this old and effective drug. ACTH does not only induce cortisol production, as previously assumed, but it also exerts anti-inflammatory actions by targeting melanocortin receptors present on immune cells. The endogenous agonists for these receptors (ACTH, α-, β-, and γ-melanocyte stimulating hormones), are also produced locally by immune cells, indicating the existence of an endogenous anti-inflammatory tissue-protective circuit involving the melanocortin system. These findings suggested that new ACTH-like melanocortin drugs devoid of steroidogenic actions, and hence side effects, could be developed. This review summarizes the actions of ACTH and melanocortin drugs, their role as endogenous pro-resolving mediators, their current clinical use and provides an overview on how recent advances on GPCR functioning may lead to a novel class of drugs.
26604187 Tumor necrosis factor inhibitors added to nonbiological immunosuppressants vs. nonbiologic 2016 Apr We aimed at detecting a signal of an increased risk of cancer in patients treated with TNF inhibitor (TNFi) and nonbiological immunosuppressant (NBIS), compared with NBIS alone for autoimmune diseases. Secondly, we aimed at comparing this risk between the different TNFis. We conducted a disproportionality analysis (case/noncase study) from the French National PharmacoVigilance Database. We selected all the reports of serious adverse drug reactions from 2000 to 2010 in patients treated with NBIS for labeled indications of TNFi. Cases were all the reports of cancer that occurred after a minimal 3-month exposure to NBIS. Noncases were all the other reports. We searched for exposure to TNFi and calculated reporting odds ratios (RORs), stratified by condition and type of cancer and adjusted by age, gender, history of cancer, type of NBIS and year of reporting. Of the 1918 reports included in the study population, 217 were cases (135 solid and 82 blood cancers). A safety signal was found in rheumatoid arthritis (RA) (ROR: 5.43, 95% CI[3.52-8.38]) particularly for nonmelanoma skin cancer (NMSC) (20.17[2.49-163.36]), and in psoriasis/psoriatic arthritis (3.45[1.09-10.92]). No signal was found in inflammatory bowel diseases (IBD) and ankylosing spondylitis, whatever the type of cancer. There was no difference between TNFis. This study puts the argument of an increased risk of cancer (particularly NMSC) in patients with rheumatoid arthritis exposed to TNFi and NBIS compared with NBIS alone, but not in IBD and ankylosing spondylitis patients. No signal was detected for melanoma potentially related to the lack of power. The signal seems similar whatever the TNFi.
26337538 Treatment patterns and annual biologic costs in US veterans with rheumatic conditions or p 2016 OBJECTIVE: To determine annual biologic drug and administration costs to the US Veterans Health Administration (VHA) per treated patient with rheumatoid arthritis (RA), psoriasis (PsO), psoriatic arthritis (PsA), or ankylosing spondylitis (AS) who received abatacept, adalimumab, certolizumab pegol, etanercept, golimumab, infliximab, rituximab, tocilizumab, or ustekinumab. METHODS: Adults with at least one biologic claim between January 1, 2008 and December 31, 2011 were included. Evidence of enrollment in the VHA was required from 365 days before (pre-index) to 360 days after (post-index) the date of the first biologic claim (index date). Included patients had pre-index diagnoses of RA, PsO, PsA, and/or AS. Drug costs were from Federal Supply Schedule or 'Big Four' in November 2014. Administration costs were VHA fixed costs for infused ($169) and subcutaneous ($25) biologics. RESULTS: Of the 20,465 patients in the analysis, 10,711 received etanercept, 7838 received adalimumab, and 1196 received infliximab as the index biologic. In these patients, across all uses studied, the VHA incurred greater annual cost per treated patient for infliximab ($18,066) compared with adalimumab ($16,523) and etanercept ($16,526). In the first year post-index, ∼80% of patients were either persistent on these index biologics or re-started these index biologics after a ≥45-day treatment gap. Other biologics comprised <5% of the study population, with sample sizes ranging from 3-374 patients each. Cost by indication for biologics used by >20 patients ranged from $15,056 (etanercept) to $17,050 (abatacept) for RA; $16,697 (adalimumab) to $33,163 (ustekinumab) for PsO; $15,035 (etanercept) to $20,465 (infliximab) for PsA; and $14,239 (etanercept) to $18,536 (infliximab) for AS. LIMITATIONS: The model was limited to the VHA. Results for biologics other than adalimumab, etanercept, and infliximab were difficult to interpret because of small sample sizes. CONCLUSIONS: Infliximab has higher cost to the VHA than adalimumab or etanercept.
26602520 Serum from patients with ankylosing spondylitis can increase PPARD, fra-1, MMP7, OPG and R 2015 Nov OBJECTIVES: To explore the effects of serum from patients with ankylosing spondylitis on the canonical Wnt/β-catenin pathway and to assess whether the serum has an osteogenic effect in MG63 cells. METHODS: MG63 cells were cultured with serum from 45 ankylosing spondylitis patients, 30 healthy controls, or 45 rheumatoid arthritis patients. The relative PPARD, fra-1, MMP7, OPG and RANKL mRNA levels were measured using quantitative real-time polymerase chain reaction. Associations between gene expression and patient demographics and clinical assessments were then analyzed. RESULTS: MG63 cells treated with serum from ankylosing spondylitis patients had higher PPARD, fra-1, MMP7 and OPG gene expression than did cells treated with serum from controls or rheumatoid arthritis patients (all p<0.05). RANKL expression was higher in MG63 cells treated with serum from patients with ankylosing spondylitis or rheumatoid arthritis than in those treated with serum from controls (both p<0.05). The OPG/RANKL ratio was also higher in MG63 cells treated with serum from ankylosing spondylitis patients than in those treated with serum from controls (p<0.05). No associations were found between the expression of the five genes and the patient demographics and clinical assessments (all p>0.05). CONCLUSIONS: Serum from ankylosing spondylitis patients increases PPARD, fra-1, MMP7, OPG and RANKL expression and the OPG/RANKL ratio in MG63 cells; these effects may be due to the stimulatory effect of the serum on the Wnt pathway.
27550297 Interleukin 26 suppresses receptor activator of nuclear factor κB ligand induced osteocla 2016 Nov OBJECTIVE: IL-26 has been shown to have high expression in RA. However, the effects of IL-26 on bone destruction in RA have not been evaluated. The aim of this study was to investigate the effects and mechanisms of IL-26 on RANK ligand (RANKL)-induced osteoclastogenesis. METHODS: We treated cells with IL-26 in RANKL-induced oseteoclastogenesis to monitor osteoclast formation by tartrate-resistant acid phosphatase (TRAP) staining. Osteoclast activity was assessed by pit formation assay and F-actin ring formation. The mechanism of the inhibition was studied by biochemical analyses such as RT-PCR, immunofluorescence staining and immunoblotting. In addition, cell viability was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. RESULTS: IL-26 inhibited RANKL-induced TRAP-positive ( )multinucleated cells and inhibited RANKL-induced nuclear factor κB (NF-κB) activation and nuclear factor of activated T cells, cytoplasmic 1 (NFATc1) nuclear translocation in RAW264.7 cells. Also, IL-26 significantly inhibited the bone-resorbing activity and F-actin ring formation ability of mature osteoclasts. Moreover, IL-26 suppressed RANKL-induced mitogen-activated protein kinase activation and NFATc1 downstream gene expression. CONCLUSION: We suggest that the inhibitory activity of IL-26 on osteoclastogenesis is via down-regulation of RANKL-induced NF-κB and NFATc1 expression. Our results suggest IL-26 as a possible new remedy against osteolytic bone destruction.
27040161 The SKG Mutation in ZAP-70 also Confers Arthritis Susceptibility in C57 Black Mouse Strain 2016 Jul Various rodent models of arthritis are essential to dissect the full complexity of human rheumatoid arthritis (RA), a common autoimmune disease affecting joints. The SKG model of arthritis originates from a spontaneous mutation in ZAP-70 found in a BALB/c colony. This mutation affects T cell selection due to reduced TCR signalling, which allows leakage of self-reactive T cells from the thymus. To further expand the practical applicability of this unique model in arthritis research, we investigated the arthritogenicity of the SKG mutation in two common black mouse strains C57BL/6.Q and C57BL/10.Q and compared to BALB/c.Q. Mice retained the reduced TCR signalling characteristic of SKG.BALB/c mice, which leads to similar alteration in thymic selection. Importantly, mice also retained susceptibility to chronic arthritis after a single injection of mannan from Saccharomyces cerevisiae, with comparable prevalence and severity regardless of the genetic background. Further characterization of CD4(+) T cells revealed a similar bias towards IL-17 production and activated T cell phenotype in all SKG strains compared to respective wild type controls. Finally, transfer of SKG thymocytes conferred susceptibility to recipients, which confirm the intrinsic defect and pathogenicity of T cells. Overall, these results underline the strong impact that the W163C ZAP-70 mutation has on T cell-driven arthritis, and they support the use of the SKG model in black mice, which is useful for further investigations of this distinctive arthritis model to better understand autoimmunity.
26834211 Efficacy and Safety of Subcutaneous and Intravenous Loading Dose Regimens of Secukinumab i 2016 Mar OBJECTIVE: To evaluate the efficacy and safety of secukinumab, a fully human antiinterleukin-17A monoclonal antibody, administered with an intravenous (IV) or subcutaneous (SC) loading regimen versus placebo, in patients with active rheumatoid arthritis (RA). METHODS: In this phase II, double-blind, double-dummy, 52-week study (ClinicalTrials.gov NCT01359943), 221 patients with inadequate response to methotrexate were randomized (2:2:1) to secukinumab, IV loading 10 mg/kg at baseline, Weeks 2 and 4, then SC 150 mg every 4 weeks (n = 88); secukinumab SC loading 150 mg once weekly for 5 weeks, then every 4 weeks (n = 89); or a matching placebo (followed by secukinumab 150 mg every 4 weeks starting Week 16; n = 44). The primary endpoint was superior efficacy of pooled secukinumab versus placebo using American College of Rheumatology 20% response (ACR20) at Week 12. RESULTS: The primary efficacy endpoint was not met: ACR20 response at Week 12 was 49.2% for pooled secukinumab versus 40.9% for placebo (p = 0.3559). These variables improved significantly with pooled secukinumab versus placebo at Week 12 (all p < 0.05): the 28-joint Disease Activity Score (DAS28), patient's and physician's global assessment of disease activity, patient's assessment of RA pain, and high-sensitivity C-reactive protein levels. Results of continuous efficacy outcomes were similar between the IV and SC loading regimens. The most frequent adverse events were infections, with similar rates across secukinumab and placebo. CONCLUSION: Although the primary endpoint (ACR20) was not met, secukinumab demonstrated improved efficacy in reducing disease activity over placebo as measured by DAS28 and other secondary endpoints.
24130267 AMPA/kainate glutamate receptors contribute to inflammation, degeneration and pain related 2015 Jan OBJECTIVES: Synovial fluid glutamate concentrations increase in arthritis. Activation of kainate (KA) and α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) glutamate receptors (GluRs) increase interleukin-6 (IL-6) release and cause arthritic pain, respectively. We hypothesised that AMPA and KA GluRs are expressed in human arthritis, and that intra-articular NBQX (AMPA/KA GluR antagonist) prevents pain and pathology in antigen-induced arthritis (AIA). METHODS: GluR immunohistochemistry was related to synovial inflammation and degradation in osteoarthritis (OA) and rheumatoid arthritis (RA). A single intra-articular NBQX injection was given at induction, and knee swelling and gait of AIA and AIA+NBQX rats compared over 21 days, before imaging, RT-qPCR, histology and immunohistochemistry of joints. Effects of NBQX on human primary osteoblast (HOB) activity were determined. RESULTS: AMPAR2 and KA1 immunolocalised to remodelling bone, cartilage and synovial cells in human OA and RA, and rat AIA. All arthritic tissues showed degradation and synovial inflammation. NBQX reduced GluR abundance, knee swelling (p<0.001, days 1-21), gait abnormalities (days 1-2), end-stage joint destruction (p<0.001), synovial inflammation (p<0.001), and messenger RNA expression of meniscal IL-6 (p<0.05) and whole joint cathepsin K (p<0.01). X-ray and MRI revealed fewer cartilage and bone erosions, and less inflammation after NBQX treatment. NBQX reduced HOB number and prevented mineralisation. CONCLUSIONS: AMPA/KA GluRs are expressed in human OA and RA, and in AIA, where a single intra-articular injection of NBQX reduced swelling by 33%, and inflammation and degeneration scores by 34% and 27%, respectively, exceeding the efficacy of approved drugs in the same model. AMPA/KA GluR antagonists represent a potential treatment for arthritis.
26714738 Dysregulation of RasGRP1 in rheumatoid arthritis and modulation of RasGRP3 as a biomarker 2015 Dec 26 BACKGROUND: B and T cells play a key role in rheumatoid arthritis (RA) pathophysiology. RasGRP1 and RasGRP3 are involved in T and B cell receptors signaling, and belong to gene combination able to predict infliximab responsiveness, leading to the question of RasGRP1 and RasGRP3 involvement in RA. METHODS: RasGRP1 and RasGRP3 expression levels were measured by qRT-PCR and/or western-blot in peripheral blood mononuclear cells (PBMCs), in T and B cells from untreated RA patients and in RA patients treated by TNFα inhibitors. T and B cells from healthy controls (HC) were cultured with TNFα, and TNFα receptors neutralizing antibodies to highlight the TNFα effects on RasGRP1 and RasGRP3 pathways. MAPK pathways and apoptosis were respectively analyzed using the Proteome Profiler arrays and flow cytometry. RESULTS: In PBMCs from RA patients, gene expression levels of RasGRP1 were invariant while RasGRP3 was downregulated under TNFα inhibitors and upregulated under TNFα. In T cells from RA patients, RasGRP1 was decreased and its gene expression level was correlated with disease activity. In T cells from HC, TNFα stimulation increased RasGRP1 gene expression level while it reduced RasGRP1 protein expression level. Bryostatin-1 experiments have confirmed that the TNFα effect observed on T cells proliferation was due to the decrease of RasGRP1 expression. Besides, RasGRP3 expression level increased in PBMCs from RA patients under TNFα and in B cells from HC leading us to conclude that RasGRP3 in B cells was modulated by TNFα. CONCLUSION: This study demonstrates RasGRP1 dysregulation in RA patients while RasGRP3 is characterized as a biomarker linked to TNFα inhibitors. After binding to TNFR1, TNFα reduced RasGRP1 protein expression resulting in inhibition of T cell activation. TRIAL REGISTRATION: Clinicaltrials.gov NCT00234234 , registered 04 November 2008; NCT00767325 , registered 05 October 2005.