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Andrew McMaster,
Maryam Jangani,
Paula Sommer,
Namshik Han,
Andy Brass,
Stephen Beesley,
Weiqun Lu,
Andrew Berry,
Andrew Loudon, Rachelle Donn,
David W Ray
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ABSTRACT: Cortisol is released in ultradian pulses. The biological relevance of the resulting fluctuating cortisol concentration has not been explored.
Determination of the biological consequences of ultradian cortisol pulsatility.
A novel flow through cell culture system was developed to deliver ultradian pulsed or continuous cortisol to cells. The effects of cortisol dynamics on cell proliferation and survival, and on gene expression were determined. In addition, effects on glucocorticoid receptor (GR) expression levels and phosphorylation, as a potential mediator, were measured.
Pulsatile cortisol caused a significant reduction in cell survival compared to continuous exposure of the same cumulative dose, due to increased apoptosis. Comprehensive analysis of the transcriptome response by microarray identified genes with a differential response to pulsatile versus continuous glucocorticoid delivery. These were confirmed with qRT-PCR. Several transcription factor binding sites were enriched in these differentially regulated target genes, including CCAAT-displacement protein (CDP). A CDP regulated reporter gene (MMTV-luc) was, as predicted, also differentially regulated by pulsatile compared to continuous cortisol delivery. Importantly there was no effect of cortisol delivery kinetics on either GR expression, or activation (GR phosphoSer(211)).
Cortisol oscillations exert important effects on target cell gene expression, and phenotype. This is not due to differences in cumulative cortisol exposure, or either expression, or activation of the GR. This suggests a novel means to regulate GR function.
PLoS ONE 01/2011; 6(1):e15766. · 4.09 Impact Factor
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ABSTRACT: Macrophage migration inhibitory factor (MIF) is a proinflammatory mediator involved in the pathogenesis of rheumatoid arthritis. This study was undertaken to identify the MIF promoter elements responsible for regulating gene expression.
Luciferase reporter gene assays were used to identify the MIF promoter sequence responsible for basal activity. Bioinformatic analysis was used to predict transcription factor binding sites, and electrophoretic mobility shift assay (EMSA) was used to demonstrate transcription factor binding. Chromatin immunoprecipitation (ChIP) was used to demonstrate transcription factor loading on the MIF promoter.
We identified the minimal promoter sequence required for basal MIF promoter activity that was also capable of conferring glucocorticoid-dependent inhibition in a T lymphocyte model cell line. Deletion studies and EMSA revealed 2 elements in the MIF promoter that were responsible for basal promoter activity. The 5' element binds CREB/activating transcription factor 1, and the 3' element is a functional hypoxia-responsive element binding hypoxia-inducible factor 1alpha. Further studies demonstrated that the cis elements are both required for glucocorticoid-dependent inhibition. ChIP demonstrated glucocorticoid-dependent recruitment of glucocorticoid receptor alpha to the MIF promoter in lymphocytes within 1 hour of treatment and a concomitant decrease in acetylated histone H3.
Our findings indicate that hypoxia and glucocorticoid signaling converge on a single element regulating MIF; this regulatory unit is a potential interacting node for microenvironment sensing of oxygen tension and glucocorticoid action in foci of inflammation.
Arthritis & Rheumatism 08/2009; 60(8):2220-31. · 7.87 Impact Factor
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Qing Jun Meng,
Andrew McMaster,
Stephen Beesley,
Wei Qun Lu,
Julie Gibbs,
Derek Parks,
Jon Collins,
Stuart Farrow, Rachelle Donn,
David Ray,
Andrew Loudon
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ABSTRACT: The nuclear receptor REV-ERBalpha is a key negative-feedback regulator of the biological clock. REV-ERBalpha binds to ROR elements of the Bmal1 (Arntl) promoter and represses Bmal1 transcription. This stabilizing negative loop is important for precise control of the circadian pacemaker. In the present study, we identified a novel synthetic REV-ERBalpha ligand, which enhances the recruitment of nuclear receptor co-repressor (NCoR) to REV-ERBalpha. In order to explore REV-ERBalpha action on resetting responses of the molecular clock, we first established the rhythmic transcription profile and expression level of REV-ERBalpha in Rat-1 fibroblasts. When applied at different phases of the circadian oscillation to cell models containing stably transfected Bmal1::Luc or Per2::Luc, the REV-ERBalpha ligand induced phase-dependent bi-directional phase shifts. When the phase changes were plotted against time, a clear phase response curve was revealed, with a significant peak-to-trough amplitude of ca. 5 hours. The phase-resetting effect was also observed when the compound was applied to primary lung fibroblasts and ectopic lung slices from transgenic PER2::Luc mice. Therefore, similar regulation of REV-ERBalpha function by endogenous ligands, such as heme, is likely to be an important mechanism for clock resetting. In addition, we identify a new means to generate phasic shifts in the clock.
Journal of Cell Science 12/2008; 121(Pt 21):3629-35. · 6.11 Impact Factor
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ABSTRACT: Macrophage migration inflammatory factor (MIF) is a proinflammatory cytokine with a unique role as the physiologic counterregulator of the immunosuppressive effects of glucocorticoids. MIF has been implicated in the pathogenesis of glomerular inflammation. The MIF promoter contains a G/C polymorphism that is functionally relevant, with the C allele being associated with higher MIF production and linked to susceptibility to inflammatory diseases. We genotyped the MIF -173 polymorphism in 257 children with idiopathic nephrotic syndrome (INS) and 355 controls. Frequency of carriers of the high-producer MIF -173*C allele was higher in patients with INS (31.7%) than in controls (22.0%) [odds ratio (OR) 1.67, p = 0.006] The MIF -173 C allele was more frequent in steroid-resistant patients (43.5%) compared with steroid responders (22.8%) (OR 2.61, p = 0.0005). This difference was particularly evident in focal segmental glomerulosclerosis patients (OR 14.0, p = 0.002). No association with response to cyclosporin A was found. Carriers of the MIF -173*C allele had a significantly higher probability of end-stage renal disease (ESRD) compared with G/G homozygous patients within 5 years from onset (log rank 5.11 p = 0.024). These results underscore the role of MIF in INS disease progression and in the response to glucocorticoid treatment and suggest that screening of MIF genotype at disease onset may identify patients requiring a more aggressive therapeutic approach.
Pediatric Nephrology 06/2008; 23(5):743-8. · 2.52 Impact Factor
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ABSTRACT: Macrophage migration inflammatory factor (MIF) is a proinflammatory cytokine with a unique role as the physiologic counterregulator
of the immunosuppressive effects of glucocorticoids. MIF has been implicated in the pathogenesis of glomerular inflammation.
The MIF promoter contains a G/C polymorphism that is functionally relevant, with the C allele being associated with higher MIF production
and linked to susceptibility to inflammatory diseases. We genotyped the MIF −173 polymorphism in 257 children with idiopathic
nephrotic syndrome (INS) and 355 controls. Frequency of carriers of the high-producer MIF −173*C allele was higher in patients
with INS (31.7%) than in controls (22.0%) [odds ratio (OR) 1.67, p = 0.006] The MIF −173 C allele was more frequent in steroid-resistant patients (43.5%) compared with steroid responders (22.8%)
(OR 2.61, p = 0.0005). This difference was particularly evident in focal segmental glomerulosclerosis patients (OR 14.0, p = 0.002). No association with response to cyclosporin A was found. Carriers of the MIF −173*C allele had a significantly
higher probability of end-stage renal disease (ESRD) compared with G/G homozygous patients within 5years from onset (log
rank 5.11 p = 0.024). These results underscore the role of MIF in INS disease progression and in the response to glucocorticoid treatment
and suggest that screening of MIF genotype at disease onset may identify patients requiring a more aggressive therapeutic
approach.
Pediatric Nephrology 04/2008; 23(5):743-748. · 2.52 Impact Factor
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ABSTRACT: To investigate whether single-nucleotide polymorphisms (SNPs) within the genes PRF1, GZMB, UNC13D, and Rab27a, which are involved in natural killer cell dysfunction and known to contribute to the risk of hemophagocytic lymphohistiocytosis (HLH), confer an increased risk of susceptibility to systemic-onset juvenile idiopathic arthritis (JIA).
Four SNPs across the PRF1 gene locus, 5 for GZMB, 7 for UNC13D, and 11 for Rab27a were investigated using MassArray genotyping in 133 UK Caucasian patients with systemic-onset JIA and 384 ethnically matched unrelated control subjects. Additional control genotypes were accessed from the data generated by the Wellcome Trust Case Control Consortium.
No significant association was found between any SNP within the 4 selected loci and systemic-onset JIA, by either single-point or haplotype analysis.
The results of this study demonstrate that genes involved in HLH do not confer a significant risk of association with systemic-onset JIA.
Arthritis & Rheumatism 04/2008; 58(3):869-74. · 7.87 Impact Factor
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Wendy Thomson,
Anne Barton,
Xiayi Ke,
Steve Eyre,
Anne Hinks,
John Bowes, Rachelle Donn,
Deborah Symmons,
Samantha Hider,
Ian N Bruce, [......],
Ann Morgan,
Paul Emery,
Angela Carter,
Sophia Steer,
Lynne Hocking,
David M Reid,
Paul Wordsworth,
Pille Harrison,
David Strachan,
Jane Worthington
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ABSTRACT: The Wellcome Trust Case Control Consortium (WTCCC) identified nine single SNPs putatively associated with rheumatoid arthritis at P = 1 x 10(-5) - 5 x 10(-7) in a genome-wide association screen. One, rs6920220, was unequivocally replicated (trend P = 1.1 x 10(-8)) in a validation study, as described here. This SNP maps to 6q23, between the genes oligodendrocyte lineage transcription factor 3 (OLIG3) and tumor necrosis factor-alpha-induced protein 3 (TNFAIP3).
Nature Genetics 01/2008; 39(12):1431-3. · 35.53 Impact Factor
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ABSTRACT: Macrophage migration inhibitory factor (MIF) is an inflammatory mediator associated with RA severity. In various diseases, MIF polymorphisms are associated with clinical response glucocorticoid (GC) treatment. It is unclear whether MIF polymorphisms determine GC response in rheumatoid arthritis (RA) and to other RA treatments. Therefore, the question of whether two functional variants in MIF are associated with the response to tumour necrosis factor (TNF)alpha-neutralising and GC treatments in RA was investigated.
Data from two cohorts of an RA registry were used. For patients who started with TNFalpha-neutralising (infliximab) or GC treatment, courses with a duration of at least 3 months were included and response to TNFalpha blockers or GC was calculated according to the European League Against Rheumatism response criteria. MIF -173G-->C genotyping was achieved using an assay-on-demand allelic discrimination assay, and alleles of the CATT repeat element were identified using a fluorescently labelled PCR primer and capillary electrophoresis. Logistic-regression modelling was used for the statistical analysis.
In total, 192 courses of oral prednisone or methylprednisolone injections in 98 patients with RA and 90 patients with RA who were on TNFalpha-neutralising treatments were documented. In all, 27% of the patients with RA were found to be heterozygous for seven CATT repeats (CATT(7)) and 31% were heterozygous for -173C. Respectively, 4% and 6% of the patients with RA were homozygous for the MIF CATT(7) repeat or the MIF -173C allele. Carrier status and homozygosity for CATT(7 )repeat and the MIF -173C allele were not associated with response to GC (odds ratios (ORs) close to 1) or to TNFalpha-neutralising treatment (ORs close to 2).
The MIF-CATT(7) repeat and the MIF-173G-->C functional variant are not strongly associated with a decreased clinical response to TNFalpha-neutralising or GC treatment in RA.
Annals of the Rheumatic Diseases 11/2007; 66(11):1525-30. · 8.73 Impact Factor
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ABSTRACT: A defect in hypothalamic-pituitary-adrenal (HPA) axis function has been suggested to contribute to susceptibility to rheumatoid arthritis (RA).
To investigate polymorphisms of the glucocorticoid receptor (GR) gene and determine any associations with RA.
Three GR polymorphisms that tag 95% of all haplotypes across the GR gene were genotyped. These are an intron B Bcl1 polymorphism, a ttg insertion/deletion within intron F (rs2307674) and the single nucleotide polymorphism (SNP) lying in the 3' untranslated region of exon 9b (rs6198). The dye terminator-based SNaPshot method or size resolution by capillary electrophoresis was performed. The study population comprised 198 UK Caucasian RA cases and 393 ethnically matched controls.
No significant single point or haplotypic associations were found for GR polymorphisms with RA susceptibility. Furthermore, no evidence for GR polymorphisms with aspects of RA severity was seen.
In this study of the most comprehensive coverage of GR polymorphisms with RA, no significant contributing role for GR polymorphisms with RA was found.
Clinical Endocrinology 10/2007; 67(3):342-5. · 3.17 Impact Factor
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ABSTRACT: To investigate SLC26A2, the gene that causes diastrophic dysplasia, in juvenile idiopathic arthritis (JIA).
Nine polymorphisms across the SLC26A2 gene locus were investigated using MassArray genotyping in 826 UK Caucasian JIA cases and 617 ethnically matched healthy controls.
Significant associations between multiple single-nucleotide polymorphisms (SNPs) across SLC26A2 and systemic-onset JIA were found. In each case, homozygosity for the minor allele conferred the increased risk of disease susceptibility: rs1541915 (odds ratio [OR] 2.3, 95% confidence interval [95% CI] 1.4-3.7, P=0.0003), rs245056 (OR 2.8, 95% CI 1.7-4.6, P=0.00002), rs245055 (OR 2.5, 95% CI 1.2-5.0, P=0.004), rs245051 (OR 2.3, 95% CI 1.4-3.7, P=0.0005), rs245076 (OR 2.7, 95% CI 1.3-5.4, P=0.0015), and rs8073 (OR 2.3, 95% CI 0.9-5.6, P=0.04).
These findings show the value of using monogenic disease loci as candidates for investigation in JIA. We identified a subgroup-specific association between SNPs within the SLC26A2 gene and systemic-onset JIA. Our findings also highlight systemic-onset JIA as being a distinctly different disease from that in the other JIA subgroups.
Arthritis & Rheumatism 05/2007; 56(4):1286-91. · 7.87 Impact Factor
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ABSTRACT: Objective
To investigate SLC26A2, the gene that causes diastrophic dysplasia, in juvenile idiopathic arthritis (JIA).Methods
Nine polymorphisms across the SLC26A2 gene locus were investigated using MassArray genotyping in 826 UK Caucasian JIA cases and 617 ethnically matched healthy controls.ResultsSignificant associations between multiple single-nucleotide polymorphisms (SNPs) across SLC26A2 and systemic-onset JIA were found. In each case, homozygosity for the minor allele conferred the increased risk of disease susceptibility: rs1541915 (odds ratio [OR] 2.3, 95% confidence interval [95% CI] 1.4–3.7, P = 0.0003), rs245056 (OR 2.8, 95% CI 1.7–4.6, P = 0.00002), rs245055 (OR 2.5, 95% CI 1.2–5.0, P = 0.004), rs245051 (OR 2.3, 95% CI 1.4–3.7, P = 0.0005), rs245076 (OR 2.7, 95% CI 1.3–5.4, P = 0.0015), and rs8073 (OR 2.3, 95% CI 0.9–5.6, P = 0.04).Conclusion
These findings show the value of using monogenic disease loci as candidates for investigation in JIA. We identified a subgroup-specific association between SNPs within the SLC26A2 gene and systemic-onset JIA. Our findings also highlight systemic-onset JIA as being a distinctly different disease from that in the other JIA subgroups.
Arthritis & Rheumatism 03/2007; 56(4):1286 - 1291. · 7.87 Impact Factor
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Rachelle Donn,
Andy Berry,
Adam Stevens,
Stuart Farrow,
Joanna Betts,
Richard Stevens,
Chris Clayton,
Jixian Wang,
Linda Warnock,
Jane Worthington,
Laurie Scott,
Simon Graham,
David Ray
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ABSTRACT: Wide variation in glucocorticoid (Gc) sensitivity exists between individuals which may influence susceptibility to, and treatment response of, inflammatory diseases. To determine a genetic fingerprint of Gc sensitivity 100 healthy human volunteers were polarized into the 10% most Gc-sensitive and 10% most Gc-resistant following a low dose dexamethasone (0.25 mg) suppression test. Gene expression profiling of primary lymphocytes identified the 98 most significantly Gc regulated genes. These genes were used to build a subnetwork of Gc signaling, with 54 genes mapping as nodes, and 6 non-Gc regulated genes inferred as signaling nodes. Twenty four of the 98 genes showed a difference in Gc response in vitro dependent on the Gc sensitivity of their donor individuals in vivo. A predictive model was built using both partial least squares discriminate analysis and support vector machines that predicted donor glucocorticoid sensitivity with 87% accuracy. Discriminating genes included bone morphogenetic protein receptor, type II (BMPRII). Transfection studies showed that BMPRII modulated Gc action. These studies reveal a broad base of gene expression that predicts Gc sensitivity and determine a Gc signaling network in human primary T lymphocytes. Furthermore, this combined gene profiling, and functional analysis approach has identified BMPRII as a modulator of Gc signaling.
The FASEB Journal 03/2007; 21(2):402-14. · 5.71 Impact Factor
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ABSTRACT: Macrophage migration inhibitory factor (MIF) is a pro-inflammatory mediator with the ability to induce various immunomodulatory responses and override glucocorticoid-driven immunosuppression. Some of these functions have been linked to the unusual enzymatic properties of the protein, namely tautomerase and oxidoreductase activities. However, there are conflicting reports regarding the functional role of these enzymatic properties in normal physiological homeostasis and disease progression. Therefore, we have produced a highly pure, virtually endotoxin-free recombinant MIF preparation and fully characterized this using a variety of biochemical and biophysical approaches. The recombinant protein, with demonstrable enzymatic activity, was then used to systematically examine the biological activity of MIF. Surprisingly, treatment with MIF alone failed to induce cytokine expression, with the exception of IL-8. However, co-treatment of lipopolysaccharide (LPS) in conjunction with MIF produced synergistic secretion of tumor necrosis factor-alpha, interleukin (IL)-1, and IL-8 compared with LPS alone. The potentiating effect of MIF was seen at physiologically relevant concentrations. These data suggest that MIF has no conventional cytokine activity but, rather, acts to modulate and amplify the response to LPS.
Journal of Biological Chemistry 11/2006; 281(40):29641-51. · 4.77 Impact Factor
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ABSTRACT: Macrophage migration inhibitory factor (MIF) is a pro-inflammatory mediator with the ability to induce various immunomodulatory
responses and override glucocorticoid-driven immunosuppression. Some of these functions have been linked to the unusual enzymatic
properties of the protein, namely tautomerase and oxidoreductase activities. However, there are conflicting reports regarding
the functional role of these enzymatic properties in normal physiological homeostasis and disease progression. Therefore,
we have produced a highly pure, virtually endotoxin-free recombinant MIF preparation and fully characterized this using a
variety of biochemical and biophysical approaches. The recombinant protein, with demonstrable enzymatic activity, was then
used to systematically examine the biological activity of MIF. Surprisingly, treatment with MIF alone failed to induce cytokine
expression, with the exception of IL-8. However, co-treatment of lipopolysaccharide (LPS) in conjunction with MIF produced
synergistic secretion of tumor necrosis factor-α, interleukin (IL)-1, and IL-8 compared with LPS alone. The potentiating effect
of MIF was seen at physiologically relevant concentrations. These data suggest that MIF has no conventional cytokine activity
but, rather, acts to modulate and amplify the response to LPS.
Journal of Biological Chemistry 10/2006; 281(40):29641-29651. · 4.77 Impact Factor
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ABSTRACT: Glucocorticoids exert diverse effects on virtually all cell types and tissues. Subtle changes in sensitivity may be generalized and congenital or acquired in a tissue-specific manner. Such changes may lead to altered susceptibility to metabolic diseases, such as ischemic heart disease, or to insensitivity to the therapeutic actions of synthetic glucocorticoids such as in inflammatory disease. This review will cover current theories of how glucocorticoids exert genetic and other congenital effects on glucocorticoid sensitivity, and acquired changes in glucocorticoid sensitivity seen principally in inflammatory and malignant disease. Recent important developments in the field include the impact of genetic variation within the glucocorticoid receptor gene, the effects of early life experience on long-term glucocorticoid sensitivity, studies identifying the role of nuclear factor κκB in modulating glucocorticoid sensitivity in vitro and in vivo, and the action of macrophage migration inhibitory factor in modulating the anti-inflammatory effects of glucocorticoids. The role of chromatin organization in regulating glucocorticoid action on proinflammatory genes is discussed, as is the regulation of glucocorticoid sensitivity in human malignancy in the context of pathogenesis and treatment response.
Expert Review of Endocrinology & Metabolism 04/2006; 1(3):403-412.
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ABSTRACT: To determine whether Wnt-1-inducible signaling pathway protein 3 (WISP3) polymorphisms are associated with susceptibility to juvenile idiopathic arthritis (JIA).
The exons and the intron/exon boundaries of the WISP3 gene were mutation-screened by denaturing high-performance liquid chromatography in 86 patients with polyarticular-course JIA (>/=5 joints affected) and 15 controls. Seven single-nucleotide polymorphisms (SNPs) were genotyped, using allelic discrimination, in a case-control study. Initially, 159 patients with polyarticular-course JIA and 263 controls were studied, followed by study of a replication cohort of 181 patients with polyarticular-course JIA and 355 controls. Available parents of patients with polyarticular-course JIA were also genotyped. Finally, other JIA subgroups were studied (initial cohort, n = 218; replication cohort, n = 213). Single-point and haplotype analysis was carried out.
Positive association with SNP WISP3*G84A was observed and replicated in 2 cohorts of patients with polyarticular-course JIA. Specifically, homozygosity of the mutant allele (WISP3*84AA) conferred a 2-fold increased risk of disease susceptibility (for the initial cohort, odds ratio [OR] 2.1, 95% confidence interval [95% CI] 1.1-4.2, P = 0.03; for the replication cohort, OR 2.0, 95% CI 1.0-4.3, P = 0.05). Strong linkage disequilibrium was observed between SNPs; however, no haplotypic effect of an order of magnitude greater than the single-point WISP3*G84A association was observed. Using the transmission disequilibrium test, a trend toward overtransmission of the WISP3*84A allele was observed in patients with polyarticular-course JIA. No association of any WISP3 polymorphism was observed in the other JIA subgroups.
Association and replication of a polymorphism within the first intron of the WISP3 gene have been shown in patients with polyarticular-course JIA. The functional significance of the WISP3*G84A SNP is being determined.
Arthritis & Rheumatism 12/2005; 52(11):3548-53. · 7.87 Impact Factor
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ABSTRACT: To study whether genetic variants of macrophage migration inhibitory factor (MIF), the MIF -173G>C and CATT(5-8) alleles, are associated with disease severity and levels of circulating MIF in patients with rheumatoid arthritis (RA).
Genotyping was performed in patients with early RA and in healthy controls. Demographic data, disease activity, and outcome measurements were compared between patients with and without the MIF variants. MIF -173G>C and CATT(5-8) polymorphisms were genotyped, and a newly developed enzyme-linked immunosorbent assay for human MIF was used. Allele and genotype distributions of the MIF -173G>C and CATT(5-8) polymorphisms were compared between patients and controls by chi-square test. Multiple regression analysis was performed to assess the independence of the MIF functional genetic variants as risk factors for radiologic joint damage.
Genotyping of the -173G>C and CATT(5-8) polymorphisms of MIF in RA patients and healthy individuals (n = 277 each) revealed similar frequencies of genotypes and haplotypes in both groups. No significant differences in demographic or clinical features were observed between RA patients carrying the MIF -173C allele or the MIF CATT7 allele or both and non-carrier RA patients. Radiologic joint damage was significantly higher in patients carrying risk alleles of the MIF -173G>C or the MIF CATT(5-8) functional variants. No synergistic effects between both genetic variants were observed. Multivariate regression analysis revealed that presence of the MIF -173C/C and MIF CATT(7/7) genotypes and having 1 MIF -173C allele were independent prognostic variables. Carriership of the MIF -173C allele (P = 0.002) or MIF CATT7 allele (P = 0.004) was associated with significantly higher circulating MIF levels compared with those in subjects having none of the risk-conferring alleles, and greater circulating MIF levels correlated with more severe radiologic joint damage (r = 0.64, P = 0.001).
The MIF polymorphisms are not associated with RA susceptibility but are associated with high levels of radiologic joint damage. High circulating MIF levels were shown to correlate strongly with radiologic joint damage, suggesting that MIF expression is genetically determined and can be used as a novel prognostic tool in RA.
Arthritis & Rheumatism 10/2005; 52(10):3020-9. · 7.87 Impact Factor
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ABSTRACT: The protein tyrosine phosphatase N22 (PTPN22) gene exhibits regulatory activities for both T cells and B cells. A missense single-nucleotide polymorphism (SNP) within this gene (rs2476601) has recently been associated with 4 autoimmune diseases: rheumatoid arthritis (RA), systemic lupus erythematosus, autoimmune thyroid disease, and type 1 diabetes mellitus, all of which are T cell-mediated and associated with the elaboration of autoantibody. The aim of this study was to investigate associations of the missense SNP of PTPN22 in a number of autoimmune diseases in the UK population, including RA, juvenile idiopathic arthritis (JIA), psoriasis, psoriatic arthritis (PsA), and multiple sclerosis (MS), some of which have not been examined previously.
The PTPN22 missense SNP was genotyped in 886 RA, 661 JIA, 279 psoriasis, 455 PsA, and 379 MS patients and in 595 healthy controls. Association with the PTPN22 SNP was analyzed by chi-square test as implemented in Stata software.
There was a significant association between the PTPN22 SNP and RA (P = 1.8 x 10(-8)) and JIA (P = 0.0005). In contrast, no association with psoriasis, PsA, or MS was detected.
We replicated the findings of a previous association with RA and identified a novel association with JIA. Together with previous data showing associations with other autoimmune diseases, our findings provide further evidence that the PTPN22 gene plays a role in the pathogenesis of a subgroup of autoimmune diseases.
Arthritis & Rheumatism 07/2005; 52(6):1694-9. · 7.87 Impact Factor
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ABSTRACT: To measure glucocorticoid receptor gamma (GRgamma) expression in transformed lymphocytes from individuals of known GR gene haplotype. Recently, a glucocorticoid receptor haplotype (GAT) has been described that associates with increased sensitivity to dexamethasone. As there is strong linkage disequilibrium across the gene, this haplotype is likely to extend through exon 3, altered splicing of which generates the GRgamma isoform, a splice variant with impaired transactivation activity. Therefore we proposed that the GR haplotype affects glucocorticoid sensitivity either by influencing GRgamma expression basally, or in response to Gc exposure.
We have measured expression of GRgamma, using a validated RT-PCR assay in human B lymphoblast cells of known haplotype under basal conditions, and after dexamethasone treatment.
The A549 human lung cell line and normal volunteers, five with the GAT GR haplotype and three with the CGA haplotype.
Relative expression of GRgamma compared to total GR mRNA.
GRgamma made up 5-6% of all the GR transcripts. There was no effect of carriage of the GR gene GAT haplotype on this expression. There was no effect of dexamethasone on relative expression of GRgamma.
We propose that the GRgamma isoform is a product of constitutive splicing, that it does not explain the GR haplotype association with altered glucocorticoid sensitivity, and is unlikely to play an important physiological role in affecting glucocorticoid sensitivity. As glucocorticoids do not affect GRgamma expression, relative to total GR, this splice variant is unlikely to influence glucocorticoid treatment response.
Clinical Endocrinology 10/2004; 61(3):327-31. · 3.17 Impact Factor
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ABSTRACT: Summaryobjective To measure glucocorticoid receptor gamma (GR) expression in transformed lymphocytes from individuals of known GR gene haplotype. Recently, a glucocorticoid receptor haplotype (GAT) has been described that associates with increased sensitivity to dexamethasone. As there is strong linkage disequilibrium across the gene, this haplotype is likely to extend through exon 3, altered splicing of which generates the GR isoform, a splice variant with impaired transactivation activity. Therefore we proposed that the GR haplotype affects glucocorticoid sensitivity either by influencing GR expression basally, or in response to Gc exposure.design We have measured expression of GR, using a validated RT–PCR assay in human B lymphoblast cells of known haplotype under basal conditions, and after dexamethasone treatment.patients The A549 human lung cell line and normal volunteers, five with the GAT GR haplotype and three with the CGA haplotype.measurements Relative expression of GR compared to total GR mRNA.results GR made up 5–6% of all the GR transcripts. There was no effect of carriage of the GR gene GAT haplotype on this expression. There was no effect of dexamethasone on relative expression of GR.conclusions We propose that the GR isoform is a product of constitutive splicing, that it does not explain the GR haplotype association with altered glucocorticoid sensitivity, and is unlikely to play an important physiological role in affecting glucocorticoid sensitivity. As glucocorticoids do not affect GR expression, relative to total GR, this splice variant is unlikely to influence glucocorticoid treatment response.
Clinical Endocrinology 09/2004; 61(3):327 - 331. · 3.17 Impact Factor
