Biomedical subjects

Ann-Kristin Ulfgren

Publications and source records attributed to Ann-Kristin Ulfgren.

13 recordsLinked to original sources

PubMed2007

Effects of intra-articular corticosteroids and anti-TNF therapy on neutrophil activation in rheumatoid arthritis.

OBJECTIVE: The pro-inflammatory calcium-binding protein S100A12 has been recently ascribed to the novel group of damage associated molecular pattern (DAMP) molecules. Serum levels of S100A12 reflect neutrophil activation during synovial inflammation. The aim of this project was to analyse the effect of intra-articular corticosteroids or systemic anti-TNF treatment on synovial expression and serum levels of S100A12 in rheumatoid arthritis (RA). METHODS: Serum and synovial tissue was obtained from 19 RA patients prior to and 2 weeks after intra-articular corticosteroid therapy. Serum was collected for 34 other patients, and in 14 of these patients synovial tissue was additionally obtained prior to and after 8 weeks of infliximab treatment. The expression of S100A12 was analysed by immunohistochemistry on frozen sections. Levels of S100A12 in serum were determined by ELISA. RESULTS: S100A12 serum levels were elevated in patients with active RA prior to therapy and decreased significantly in patients who responded to treatment in both patient groups, but not in non-responders. The synovial expression of S100A12 was reduced 2 weeks after successful intra-articular corticosteroid treatment. A similar decrease in local expression was found after 8 weeks of successful infliximab treatment. CONCLUSIONS: Successful treatment of RA leads to downregulation of the DAMP protein S100A12. Expression and secretion of S100A12 is rapidly diminished after therapy with intra-articular corticosteroids or infliximab. Taking these findings together, decreasing serum concentrations of S100A12 could reflect alleviated synovial neutrophil activation during successful anti-inflammatory therapy in RA.

Adult↗

PubMed2006

Variability in synovial inflammation in rheumatoid arthritis investigated by microarray technology.

In recent years microarray technology has been used increasingly to acquire knowledge about the pathogenic processes involved in rheumatoid arthritis. The present study investigated variations in gene expression in synovial tissues within and between patients with rheumatoid arthritis. This was done by applying microarray technology on multiple synovial biopsies obtained from the same knee joints. In this way the relative levels of intra-patient and inter-patient variation could be assessed. The biopsies were obtained from 13 different patients: 7 by orthopedic surgery and 6 by rheumatic arthroscopy. The data show that levels of heterogeneity varied substantially between the biopsies, because the number of genes found to be differentially expressed between pairs of biopsies from the same knee ranged from 6 to 2,133. Both arthroscopic and orthopedic biopsies were examined, allowing us to compare the two sampling methods. We found that the average number of differentially expressed genes between biopsies from the same patient was about three times larger in orthopedic than in arthroscopic biopsies. Using a parallel analysis of the tissues by immunohistochemistry, we also identified orthopedic biopsies that were unsuitable for gene expression analysis of synovial inflammation due to sampling of non-inflamed parts of the tissue. Removing these biopsies reduced the average number of differentially expressed genes between the orthopedic biopsies from 455 to 171, in comparison with 143 for the arthroscopic biopsies. Hierarchical clustering analysis showed that the remaining orthopedic and arthroscopic biopsies had gene expression signatures that were unique for each patient, apparently reflecting patient variation rather than tissue heterogeneity. Subsets of genes found to vary between biopsies were investigated for overrepresentation of biological processes by using gene ontology. This revealed representative 'themes' likely to vary between synovial biopsies affected by inflammatory disease.

Aged↗

PubMed2006

Anti-tumor necrosis factor therapy increases synovial osteoprotegerin expression in rheumatoid arthritis.

OBJECTIVE: Treatment of rheumatoid arthritis (RA) with tumor necrosis factor (TNF)-blocking agents, including etanercept and infliximab, has resulted in reductions in the radiographic progression of RA. However, the exact mechanism by which this protection occurs has not been determined. In order to add to such knowledge, we investigated the effect of anti-TNF therapy on the expression of osteoprotegerin (OPG) and receptor activator of NF-kappaB ligand (RANKL) in synovial tissue. METHODS: The expression of OPG and RANKL in synovial biopsy specimens was evaluated by immunohistochemistry. Serial synovial biopsy specimens were obtained from 18 patients with RA, before and after treatment with etanercept (9 patients) or infliximab (9 patients). Biopsy specimens were evaluated by double-blind semiquantitative analysis and image analysis. The in vitro effect of TNF antagonists on the RANKL/OPG expression in osteoblasts and endothelial cells was evaluated by Western blotting. Statistical analysis was performed using Wilcoxon's signed rank test, followed by the Bonferroni correction for multiple comparisons of paired samples. The results of in vitro experiments were evaluated by one-way analysis of variance, with Tukey's post hoc test. RESULTS: Treatment with both infliximab and etanercept increased the expression of OPG in synovial tissue. After 8 weeks of treatment, neither infliximab nor etanercept influenced RANKL expression. In both groups of patients, the RANKL:OPG ratio decreased following therapy. In vitro, both of the TNF antagonists mimicked the in vivo effect, inducing a decrease in the RANKL:OPG ratio in TNF-primed osteoblasts and endothelial cells. CONCLUSION: Therapy with TNF antagonists in RA modulates the OPG/RANKL system, a potential mechanism that could explain the retardation of radiographic damage observed following anti-TNF therapy.

Adult↗

PubMed2006

A new model for an etiology of rheumatoid arthritis: smoking may trigger HLA-DR (shared epitope)-restricted immune reactions to autoantigens modified by citrullination.

OBJECTIVE: To investigate whether smoking and HLA-DR shared epitope (SE) genes may interact in triggering immune reactions to citrulline-modified proteins. METHODS: In a case-control study involving patients with recent-onset rheumatoid arthritis (RA), we studied interactions between a major environmental risk factor (smoking), major susceptibility genes included in the SE of HLA-DR, and the presence of the most specific autoimmunity known for RA (i.e., antibodies to proteins modified by citrullination). Immunostaining for citrullinated proteins in cells from bronchoalveolar lavage fluid was used to investigate whether smoking is associated with citrullination in the lungs. RESULTS: Previous smoking was dose-dependently associated with occurrence of anticitrulline antibodies in RA patients. The presence of SE genes was a risk factor only for anticitrulline-positive RA, and not for anticitrulline-negative RA. A major gene-environment interaction between smoking and HLA-DR SE genes was evident for anticitrulline-positive RA, but not for anticitrulline-negative RA, and the combination of smoking history and the presence of double copies of HLA-DR SE genes increased the risk for RA 21-fold compared with the risk among nonsmokers carrying no SE genes. Positive immunostaining for citrullinated proteins was recorded in bronchoalveolar lavage cells from smokers but not in those from nonsmokers. CONCLUSION: We identified an environmental factor, smoking, that in the context of HLA-DR SE genes may trigger RA-specific immune reactions to citrullinated proteins. These data thus suggest an etiology involving a specific genotype, an environmental provocation, and the induction of specific autoimmunity, all restricted to a distinct subset of RA.

Adolescent↗

PubMed2006

Intraarticular corticosteroids decrease synovial RANKL expression in inflammatory arthritis.

OBJECTIVE: Intraarticular corticosteroids are frequently used as successful adjuvant therapy for inflammatory arthritides, but little is known about their effects on molecules that regulate bone biology. We undertook this study to investigate the effect of intraarticular corticosteroids on the synovial expression of RANKL and osteoprotegerin (OPG). METHODS: We evaluated RANKL, OPG, and surface marker expression by immunohistochemical methods in synovial knee biopsy samples obtained from 13 patients with inflammatory arthritis before and 2 weeks following intraarticular injection of triamcinolone hexacetonide. We further investigated the effect of dexamethasone (DEX) on RANKL expression by lymphocytes from rheumatoid arthritis synovial fluids (RA SF), using flow cytometric analysis. Finally, we evaluated the in vitro effect of DEX on RANKL and OPG expression in osteoblast-like cells, by Western blotting. RESULTS: Intraarticular corticosteroids induced a decrease in the number of synovial T cells without influencing the number of macrophages, evaluated as both CD68+ and CD163+ cells. This change was paralleled by a decrease of synovial RANKL expression with a concomitant reduction of the RANKL:OPG ratio. DEX down-regulated RANKL expression on lymphocytes derived from RA SF. Moreover, in vitro pretreatment of osteoblast-like cells with tumor necrosis factor favored an antiresorptive effect of DEX treatment through a similar down-regulation of RANKL expression. CONCLUSION: The decrease in inflammation attributed to intraarticular corticosteroids is accompanied by down-modulation of bone destruction markers. These findings offer a rationale for the beneficial effect of corticosteroids on joint erosion in arthritis.

Adrenal Cortex Hormones↗

PubMed2006

Inflammatory cell and cytokine patterns in patients with chronic polyarthritis and temporomandibular joint involvement.

OBJECTIVE: To investigate the occurrence of selected markers for inflammatory cells and cytokines in patients with chronic polyarthritis (CPA) and temporomandibular joint (TMJ) involvement. MATERIAL AND METHODS: Eleven patients (11 joints) with CPA and TMJ disorder were included in the study. Synovial specimens were obtained during TMJ open surgery and these were subjected to immunohistochemistry on frozen sections post-fixed with paraformaldehyde and with the cell membranes permeabilized by saponin. In all patients, the cytokines IL-1alpha, IL-1beta, IL-1ra, TNFalpha, IFNgamma, IL2, and TGFbeta were investigated using specific antibodies. The occurrence of macrophages and T-lymphocytes was investigated using immunohistochemistry with monoclonal antibodies against antigens CD68 and CD45RO, respectively. In addition, PCNA was used as a marker for cell proliferation. RESULTS: Staining of IL-1alpha, IL-1, and TGF was seen in all 11 specimens, IFN? in 1, TNFalpha in 4, and IL-2 in none. CD45RO-positive T cells were detected in 7 specimens, CD68-positive macrophages in 6, and cell proliferation seen with PCNA was noted in 8. CONCLUSIONS: The predominant cytokines of TMJ CPA were IL-1alpha, IL-1beta, and TGFbeta, and there appeared to be no differences between the subgroups (rheumatoid arthritis, psoriatic arthritis, and ankylosing spondylitis) involved. Moreover, the cytokine pattern of TMJ CPA patients seemed to differ from patients with osteoarthritis, as shown in our previous study. The main difference was the absence of IFNgamma and TNFalpha in TMJ CPA patients and a stronger TGFbeta and IL-1alpha expression.

Adult↗

PubMed2006

Synovial expression of IL-15 in rheumatoid arthritis is not influenced by blockade of tumour necrosis factor.

Blockade of tumour necrosis factor (TNF) is an effective treatment in rheumatoid arthritis (RA), but both non-responders and partial responders are quite frequent. This suggests that other pro-inflammatory cytokines may be of importance in the pathogenesis of RA and as possible targets for therapy. In this study we investigated the effect of TNF blockade (infliximab) on the synovial expression of IL-15 in RA in relation to different cell types and expression of other cytokines, to elucidate whether or not IL-15 is a possible target for therapy, independently of TNF blockade. Two arthroscopies with multiple biopsies were performed on nine patients with RA and knee-joint synovitis before and after three infusions of infliximab (3 mg/kg). Synovial biopsies were analysed with immunohistochemistry for expression of IL-15, TNF, IL-1alpha, IL-1ss and IFN-gamma, and for the cell surface markers CD3, CD68 and CD163. Stained synovial biopsy sections were evaluated by computerized image analysis. IL-15 expression was detected in all synovial biopsies taken at baseline. After infliximab therapy, the expression of IL-15 was increased in four patients and reduced in five. Synovial expression of IL-15 was not correlated with any CD marker or with the presence of any other cytokine. Synovial cellularity was decreased after 8 to 10 weeks of treatment with a significant reduction of the CD68-positive synovial cells, whereas no significant change was seen in the number of CD3-positive T cells and CD163-expressing macrophages. The number of TNF-producing cells in the synovial tissue at baseline was correlated with a good response to therapy. Thus, in this study the synovial expression of IL-15 in RA was not consistently influenced by TNF blockade, being apparently independent of TNF expression in the synovium. Consequently, we propose that IL-15 should remain as a therapeutic target in RA, regardless of the response to TNF blockade.

Antibodies, Monoclonal↗

PubMed2006

Effect of infliximab on mRNA expression profiles in synovial tissue of rheumatoid arthritis patients.

We examined the gene expression profiles in arthroscopic biopsies retrieved from 10 rheumatoid arthritis patients before and after anti-TNF treatment with infliximab to investigate whether such profiles can be used to predict responses to the therapy, and to study effects of the therapy on the profiles. Responses to treatment were assessed using European League Against Rheumatism response criteria. Three patients were found to be good responders, five patients to be moderate responders and two patients to be nonresponders. The TNF-alpha status of the biopsies from each of the patients before treatment was also investigated immunohistochemically, and it was detected in biopsies from four of the patients, including all three of the good responders. The gene expression data demonstrate that all patients had unique gene expression signatures, with low intrapatient variability between biopsies. The data also revealed significant differences between the good responding and nonresponding patients (279 differentially expressed genes were detected, with a false discovery rate < 0.025). Among the identified genes we found that MMP-3 was significantly upregulated in good responders (log2 fold change, 2.95) compared with nonresponders, providing further support for the potential of MMP-3 as a marker for good responses to therapy. An even more extensive list of 685 significantly differentially expressed genes was found between patients in whom TNF-alpha was found and nonresponders, indicating that TNF-alpha could be an important biomarker for successful infliximab treatment. Significant differences were also observed between biopsies taken before and after anti-TNF treatment, including 115 differentially expressed genes in the good responding group. Interestingly, the effect was even stronger in the group in which TNF-alpha was immunohistochemically detected before therapy. Here, 1,058 genes were differentially expressed, including many that were novel in this context (for example, CXCL3 and CXCL14). Subsequent Gene Ontology analysis revealed that several 'themes' were significantly over-represented that are known to be affected by anti-TNF treatment in inflammatory tissue; for example, immune response (GO:0006955), cell communication (GO:0007154), signal transduction (GO:0007165) and chemotaxis (GO:0006935). No genes reached statistical significance in the moderately responding or nonresponding groups. In conclusion, this pilot study suggests that further investigation is warranted on the usefulness of gene expression profiling of synovial tissue to predict and monitor the outcome of rheumatoid arthritis therapies.

Adult↗

PubMed2005

Intraarticular glucocorticoid treatment reduces inflammation in synovial cell infiltrations more efficiently than in synovial blood vessels.

OBJECTIVE: To investigate whether intraarticular (IA) glucocorticoid (GC) therapy diminishes synovial cell infiltration, vascularity, expression of proinflammatory cytokines, and adhesion molecule levels in patients with chronic arthritides. METHODS: Thirty-one patients with chronic arthritides received a single IA injection of triamcinolone hexacetonide to treat active large-joint inflammation. Synovial biopsy specimens were obtained with arthroscopic guidance before and 9-15 days after injection. The presence of T lymphocytes, macrophages, intercellular adhesion molecule 1 (ICAM-1), vascular endothelial growth factor (VEGF), the pan-endothelial marker CD31, and the proinflammatory cytokines interleukin-1alpha (IL-1alpha), IL-1beta, tumor necrosis factor (TNF), and high mobility group box chromosomal protein 1 (HMGB-1) was studied by immunohistochemistry and real-time reverse transcriptase-polymerase chain reaction. RESULTS: IA GC treatment resulted in good clinical response in 29 of 31 joints. After therapeutic intervention, the number of synovial T lymphocytes declined, whereas the number of macrophages remained unchanged. Overall synovial protein expression of TNF, IL-1beta, extranuclear HMGB-1, VEGF, and ICAM-1 was reduced at followup tissue sampling, while no significant effects were observed regarding vascularity. In contrast, expression of IL-1alpha, VEGF, and cytoplasmic HMGB-1 protein in vascular endothelial cells was not affected. GC therapy down-regulated levels of messenger RNA encoding IL-1alpha and IL-1beta, but not TNF or HMGB-1. CONCLUSION: Synovial cell infiltration and proinflammatory cytokine expression were affected in a multifaceted manner by IA GC treatment. Marked reduction of synovial T lymphocytes, TNF, IL-1beta, extranuclear HMGB-1, ICAM-1, and VEGF occurred in association with beneficial clinical effects. Unexpectedly, macrophage infiltration and proinflammatory endothelial cytokine expression remained unchanged. These findings may reflect mechanisms controlling the transiency of clinical improvement frequently observed after IA GC injection.

Adult↗

PubMed2005

The effect of orally and vaginally administered misoprostol on inflammatory mediators and cervical ripening during early pregnancy.

OBJECTIVES: The objective of the present study was to investigate the effect of vaginally and orally administered misoprostol on the local cervical inflammatory response. METHODS: Healthy women with a normal intrauterine pregnancy between 8 and 12 weeks of gestation presenting for an elective termination of pregnancy by vacuum aspiration were recruited into a cohort study with a control and a treatment group. In the treatment group, the women were randomized to misoprostol, 400 mug, given either orally or vaginally 3 h before surgery. Immunohistochemistry staining of CD45, CD68, MMP 8, MMP 9, TIMP 1 and TIMP 2 were assessed in cervical biopsies obtained directly prior to mechanical cervical dilatation and vacuum aspiration. RESULTS: In the treatment group, there was a greater amount of CD45-positive cells in the subepithelium region of the cervix compared to the control group. The staining of CD68 was similar in both groups. The immunostaining of MMP 8 and MMP 9 was greater in the treatment group, while the expression of TIMP 1 and TIMP 2 did not differ between control and treatment groups. CONCLUSIONS: Compared to untreated controls, treatment with misoprostol was associated with a greater expression of inflammatory cells. It could be hypothesized that administration of misoprostol mimics the cervical ripening at term pregnancy by a possible influx and activation of inflammatory cells, which increases MMP 8 and MMP 9 and thereby leads to the degradation of collagen and cervical softening.

Abortifacient Agents, Nonsteroidal↗

PubMed2005

Synovial tissue analysis in clinical trials.

Synovial tissue analysis has considerable potential for future randomized controlled trials (RCT). The synovial membrane is the target tissue in treatment strategies of rheumatoid arthritis and other arthropathies. Effective modulation of synovitis is critical when attempting to control symptoms and signs, to prevent joint damage, and to maintain function. In RCT, the systematic evaluation of changes in synovial tissue after commencing treatment enables identification of an early therapeutic effect, using relatively small numbers of patients. This special interest group is working on establishing the evidence to have this endpoint meet the OMERACT filter criteria.

Antirheumatic Agents↗

PubMed2004

Decreased binding of annexin v to endothelial cells: a potential mechanism in atherothrombosis of patients with systemic lupus erythematosus.

OBJECTIVE: The cause of the exceedingly high risk of atherothrombosis in systemic lupus erythematosus (SLE) is not clear but antiphospholipid antibodies (aPL) and potentially antithrombotic annexin V have been implicated. METHODS AND RESULTS: Twenty-six women (52+/-8.2 years) with SLE and a history of cardiovascular disease (CVD) (SLE cases) were compared with 26 women with SLE but no CVD (SLE controls) and 26 healthy women (population controls). Common carotid intima-media thickness (IMT) was determined by B-mode ultrasound as a surrogate measure of atherosclerosis. Annexin V binding to human umbilical vein endothelial cells (HUVECs) as determined by flow cytometry after 24-hour culture with plasma was decreased when plasma from SLE cases was used (SLE cases versus population controls: P=0.002; SLE cases versus SLE controls P=0.02). Antibodies against cardiolipin were among IgG antibodies causing decreased binding. There was a positive association between annexin V binding and IMT (R=0.73; P<0.001) among SLE cases. Immunohistochemical analysis revealed presence of annexin V in all human atherosclerotic plaques tested, especially at sites prone to rupture. CONCLUSIONS: Decreased annexin V binding to endothelium caused by antibodies may represent a novel mechanism of atherothrombosis. We hypothesize that even though annexin V may promote plaque growth at some disease stages, it may also stabilize plaque.

Annexin A5↗

PubMed2004

Down-regulation of the aberrant expression of the inflammation mediator high mobility group box chromosomal protein 1 in muscle tissue of patients with polymyositis and dermatomyositis treated with corticosteroids.

OBJECTIVE: High mobility group box chromosomal protein 1 (HMGB-1) is an endogenous nuclear protein that can be translocated to the cytoplasm and then released extracellularly. It can induce tumor necrosis factor and interleukin-1 production in myeloid cells. Increased expression of these 2 cytokines has been observed in muscle tissue of patients with polymyositis (PM) and dermatomyositis (DM). The present study was therefore undertaken to investigate how HMGB-1 is expressed in muscle tissue of patients with myositis and, if so, whether such expression is modulated by prednisolone therapy. METHODS: Muscle biopsy specimens from 5 patients with PM and 4 patients with DM, obtained before and 3-6 months after initiation of prednisolone therapy, were assessed by conventional microscopic evaluation and computerized image analysis, and HMGB-1 expression was investigated by immunohistochemical staining. Muscle biopsy specimens from 7 healthy controls were also studied. RESULTS: Cytoplasmic HMGB-1 expression was detected in infiltrating rounded mononuclear cells, vascular endothelial cells, and muscle fibers of PM and DM patients. Extracellular staining surrounding the inflammatory cells was also observed. After treatment with high-dose prednisolone, cytoplasmic and extracellular HMGB-1 expression was significantly reduced, coinciding mainly with a decreased number of infiltrating inflammatory cells. Cytoplasmic HMGB-1 expression was still evident in endothelial cells and muscle fibers. No HMGB-1 expression was observed in muscle tissue from healthy controls. CONCLUSION: The cytoplasmic and extracellular distribution of HMGB-1 in muscle tissue may indicate an important role of this proinflammatory molecule in the pathogenesis of PM and DM. Furthermore, our findings indicate that systemically administered high-dose corticosteroids selectively down-regulate aberrant expression of HMGB-1 in mononuclear inflammatory cells in vivo.

Adult↗