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Publications (2)12.38 Total impact

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    ABSTRACT: Rheumatoid arthritis (RA) is a chronic inflammatory joint disease and is associated with an increased cardiovascular (CV) risk. Interferons (IFNs), especially IFNβ, might play a role in atherosclerosis as they are known inhibitors of vascular smooth muscle cell proliferation and intimal hyperplasia. We studied whether functional relevant SNPs in the interferon regulatory factor 5 (IRF5) gene are associated with carotid intima media thickness (cIMT), a surrogate maker for CV disease. In 353 RA patients of the CARRÉ study, IRF5 SNPs rs2004640 and rs4728142 were determined using Taqman Genotyping assay. cIMT was determined in a subgroup of 101 patients by B-mode ultrasonography. Linear regression analyses were used to investigate the association between cIMT and IRF5 genotypes, adjusting for demographic and cardiovascular risk factors. Patients homozygous for rs2004640 G-allele have higher cIMT compared to those homozygote for the T-allele (p = 0.019) and a trend towards a higher cIMT was observed (p = 0.103) for patients homozygous for the rs4728142 G-allele versus patients with the AA-genotype. Age was an effect-modifier for this association. Linear regression analysis in patients older than 60 years showed that the rs2004640 GG-genotype was associated with higher cIMT (regression coefficient 0.107 (C. I. 0.008; 0.205), p = 0.035) compared to the TT-genotype. This remained significant after adjustment for traditional risk factors (regression coefficient 0.111 (C. I.0.02; 0.202), p = 0.020). We demonstrate that the IRF5 gene variant rs2004640 is associated with preclinical atherosclerosis in RA patients, independent of traditional cardiovascular risk factors. These results might implicate a role for type I IFN in modulating CV disease features in RA.
    Annals of the rheumatic diseases 03/2014; 73 Suppl 1:A34. · 8.11 Impact Factor
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    ABSTRACT: B cell depletion therapy is efficacious in rheumatoid arthritis (RA) patients failing on tumor necrosis factor (TNF) blocking agents. However, approximately 40% to 50% of rituximab (RTX) treated RA patients have a poor response. We investigated whether baseline gene expression levels can discriminate between clinical non-responders and responders to RTX. In 14 consecutive RA patients starting on RTX (test cohort), gene expression profiling on whole peripheral blood RNA was performed by Illumina® HumanHT beadchip microarrays. Supervised cluster analysis was used to identify genes expressed differentially at baseline between responders and non-responders based on both a difference in 28 joints disease activity score (ΔDAS28 < 1.2) and European League against Rheumatism (EULAR) response criteria after six months RTX. Genes of interest were measured by quantitative real-time PCR and tested for their predictive value using receiver operating characteristics (ROC) curves in an independent validation cohort (n = 26). Genome-wide microarray analysis revealed a marked variation in the peripheral blood cells between RA patients before the start of RTX treatment. Here, we demonstrated that only a cluster consisting of interferon (IFN) type I network genes, represented by a set of IFN type I response genes (IRGs), that is, LY6E, HERC5, IFI44L, ISG15, MxA, MxB, EPSTI1 and RSAD2, was associated with ΔDAS28 and EULAR response outcome (P = 0.0074 and P = 0.0599, respectively). Based on the eight IRGs an IFN-score was calculated that reached an area under the curve (AUC) of 0.82 to separate non-responders from responders in an independent validation cohort of 26 patients using Receiver Operator Characteristics (ROC) curves analysis according to ΔDAS28 < 1.2 criteria. Advanced classifier analysis yielded a three IRG-set that reached an AUC of 87%. Comparable findings applied to EULAR non-response criteria. This study demonstrates clinical utility for the use of baseline IRG expression levels as a predictive biomarker for non-response to RTX in RA.
    Arthritis research & therapy 04/2012; 14(2):R95. · 4.27 Impact Factor