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IFN Pathway (ifn + pathway)
Selected AbstractsHepatitis C virus replication is inhibited by 22,-methoxyolean-12-ene-3,, 24(4,)-diol (ME3738) through enhancing interferon-,,HEPATOLOGY, Issue 1 2008Yoichi Hiasa A derivative of soyasapogenol, 22,-methoxyolean-12-ene-3,, 24(4,)-diol (ME3738), ameliorates liver injury induced by Concanavalin A in mice. We examined whether ME3738 has independent antiviral effects against hepatitis C virus (HCV) using an established HCV replication model that expresses the full-length genotype 1a HCV complementary DNA plasmid (pT7-flHCV-Rz) under the control of a replication-defective adenoviral vector expressing T7 polymerase. Hepatocellular carcinoma (HepG2) cells, human hepatoma (Huh7) cells, or monkey kidney (CV-1) cells were transfected with pT7-flHCV-Rz, and infected with adenoviral vector expressing T7 polymerase. ME3738 or interferon-, (IFN-,) was added thereafter and then protein and RNA were harvested from the cells at 9 days after infection. HCV-positive and HCV-negative strands were measured by real-time reverse-transcription polymerase chain reaction and HCV core protein expression was measured using an enzyme-linked immunosorbent assay. The messenger RNA levels of innate antiviral response-related genes were assessed using real-time reverse-transcription polymerase chain reaction. ME3738 dose-dependently reduced HCV-RNA and core protein in hepatocyte-derived cell lines. The antiviral effect was more pronounced in HepG2 than in Huh7 cells. ME3738 increased messenger RNA levels of interferon-, (IFN-,) and of IFN-stimulated genes (2,-5, oligoadenylate synthetase, myxovirus resistance protein A [MxA]). Interferon-, knockdown by small interfering RNA abrogated the anti-HCV effect of ME3738. Moreover, the anti-HCV effects were synergistic when ME3738 was combined with IFN-,. Conclusion: ME3738 has antiviral effects against HCV. The enhancement of autocrine IFN-, suggests that ME3738 exerts antiviral action along the type I IFN pathway. This anti-HCV action by ME3738 was synergistically enhanced when combined with IFN-,. ME3738 might be a useful anti-HCV drug either with or without IFN-,. (HEPATOLOGY 2008.) [source] Gene Expression Profiling in Paget's Disease of Bone: Upregulation of Interferon Signaling Pathways in Pagetic Monocytes and Lymphocytes,,§JOURNAL OF BONE AND MINERAL RESEARCH, Issue 2 2008Zsolt B Nagy Abstract We examined the gene expression profile of genes involved in bone metabolism in 23 patients with PD compared with 23 healthy controls. We found a significant overexpression of the genes of the IFN pathway along with a downregulation of tnf-,. Our result suggest that IFN-mediated signaling may play important roles in aberrant osteoclastogenesis of PD. Introduction: Paget's disease of bone (PD) is characterized by focal regions of highly exaggerated bone remodeling and aberrant osteoclastogenesis. Under physiological conditions, circulating monocytes may serve as early progenitors of osteoclasts and along with peripheral blood lymphocytes produce a wide variety of factors important in bone metabolism. Nevertheless, little is known about the roles of circulating monocytes and lymphocytes in relation to the pathological bone turnover in PD. Materials and Methods: In this study, we aimed at investigating the gene expression pattern of PD using quantitative real-time PCR in monocytes and lymphocytes isolated from peripheral blood mononuclear cells (PBMCs). Fifteen genes known to be involved in osteoclastogenesis were studied in cells from 23 patients with PD and in cells from 23 healthy controls. Eight human genes including ifn-, (3.48-fold, p < 0.001), ifn-, (2.68-fold, p < 0.001), ifn-, (1.98-fold, p = 0.002), p38 ,2 mapk (2.47-fold, p = 0.002), ifn-,r1 (2.03-fold, p = 0.01), ifn-,r2 (1.81-fold, p = 0.02), stat1 (1.57-fold, p = 0.037), and tnf-, (,2.34, p < 0.001) were found to be significantly altered in pagetic monocytes compared with monocytes of healthy controls. Results: In pagetic lymphocytes, significant changes in the expression of ifn-, (2.17-fold, p < 0.001), ifn-, (2.13-fold, p = 0.005), ifn-, (1.89-fold, p < 0.001), ifn-,r1 (1.02-fold, p = 0.04), ifn-,r2 (1.01-fold, p = 0.031), stat2 (1.79-fold, p < 0.001), and tnf-, (,1.49, p < 0.001) were found compared with lymphocytes of healthy controls. Furthermore, IFN-, protein was significantly elevated in the sera of PD patients (18.7 ± 6.69 pg/ml) compared with healthy controls (3.87 ± 6.48 pg/ml, p = 0.042). Conclusions: In conclusion, our data suggest that novel pathways mainly related to the IFN-mediated signaling may play important roles in the aberrant osteoclastogenesis of PD. [source] MicroRNA-146a contributes to abnormal activation of the type I interferon pathway in human lupus by targeting the key signaling proteinsARTHRITIS & RHEUMATISM, Issue 4 2009Yuanjia Tang Objective MicroRNA have recently been identified as regulators that modulate target gene expression and are involved in shaping the immune response. This study was undertaken to investigate the contribution of microRNA-146a (miR-146a), which was identified in the pilot expression profiling step, to the pathogenesis of systemic lupus erythematosus (SLE). Methods TaqMan microRNA assays of peripheral blood leukocytes were used for comparison of expression levels of microRNA between SLE patients and controls. Transfection and stimulation of cultured cells were conducted to determine the biologic function of miR-146a. Bioinformatics prediction and validation by reporter gene assay and Western blotting were performed to identify miR-146a targets. Results Profiling of 156 miRNA in SLE patients revealed the differential expression of multiple microRNA, including miR-146a, a negative regulator of innate immunity. Further analysis showed that underexpression of miR-146a negatively correlated with clinical disease activity and with interferon (IFN) scores in patients with SLE. Of note, overexpression of miR-146a reduced, while inhibition of endogenous miR-146a increased, the induction of type I IFNs in peripheral blood mononuclear cells (PBMCs). Furthermore, miR-146a directly repressed the transactivation downstream of type I IFN. At the molecular level, miR-146a could target IFN regulatory factor 5 and STAT-1. More importantly, introduction of miR-146a into the patients' PBMCs alleviated the coordinate activation of the type I IFN pathway. Conclusion The microRNA miR-146a is a negative regulator of the IFN pathway. Underexpression of miR-146a contributes to alterations in the type I IFN pathway in lupus patients by targeting the key signaling proteins. The findings provide potential novel strategies for therapeutic intervention. [source] | ||||||||||