Project description:PGE2 is a major mediator of inflammation and is present at high concentrations in the synovial fluid of rheumatoid arthritis (RA) patients. PGE2, acting through the EP4 receptor, has both pro- and anti-inflammatory roles in vivo. To shed light on this dual role of PGE2, we investigated its effects in whole blood and in primary human fibroblast-like synoviocytes. Gene expression analysis in human leukocytes, confirmed at the protein level, revealed an EP4-dependent inhibition of the expression of genes involved in the IFN-gamma activation pathway, including IFN-gamma itself. This effect of the PGE2/EP4 axis on IFN-gamma is a reciprocal phenomenon since IFN-gamma blocks PGE2 release and blocks EP receptor expression. The mutually antagonistic relationship between IFN-gamma and PGE2 extends to downstream cytokine- and chemokine-release; PGE2 counters the effects of IFN-gamma, on the release of IP-10, IL-8, TNFalpha and IL-1beta. To gain further insight into IFN-gamma-mediated cellular events in rheumatoid arthritis, we assessed the effects of IFN-gamma on gene expression in fibroblast-like synoviocytes. We observed an IFN-gamma-dependent up-regulation of macrophage-attracting chemokines, and down-regulation of metalloprotease expression. These results suggest the existence of a mutually antagonistic relationship between PGE2 and IFN-gamma which may represent a fundamental mechanism of immune control in diseases such as RA. For details, see Mathieu MC et al, EJI, issue 7, 2008
Project description:PGE2 is a major mediator of inflammation and is present at high concentrations in the synovial fluid of rheumatoid arthritis (RA) patients. PGE2, acting through the EP4 receptor, has both pro- and anti-inflammatory roles in vivo. To shed light on this dual role of PGE2, we investigated its effects in whole blood and in primary human fibroblast-like synoviocytes. Gene expression analysis in human leukocytes, confirmed at the protein level, revealed an EP4-dependent inhibition of the expression of genes involved in the IFN-gamma activation pathway, including IFN-gamma itself. This effect of the PGE2/EP4 axis on IFN-gamma is a reciprocal phenomenon since IFN-gamma blocks PGE2 release and blocks EP receptor expression. The mutually antagonistic relationship between IFN-gamma and PGE2 extends to downstream cytokine- and chemokine-release; PGE2 counters the effects of IFN-gamma, on the release of IP-10, IL-8, TNFalpha and IL-1beta. To gain further insight into IFN-gamma-mediated cellular events in rheumatoid arthritis, we assessed the effects of IFN-gamma on gene expression in fibroblast-like synoviocytes. We observed an IFN-gamma-dependent up-regulation of macrophage-attracting chemokines, and down-regulation of metalloprotease expression. These results suggest the existence of a mutually antagonistic relationship between PGE2 and IFN-gamma which may represent a fundamental mechanism of immune control in diseases such as RA.
Project description:To investigate the effects of soluble factors produced by synovial CD8 T cells, we stimulated human rheumatoid arthritis (RA) synovial fibroblasts with supernatants from synovial fluid CD8 T cells, blood CD8 T cells, or synovial fluid CD4 T cells stimulated with anti-CD3/CD28 antibody-coated beads. For comparison, we stimulated RA synovial fibroblasts with recombinant TNF or interferon-gamma or T cell supernatants pre-incubated with TNF-blocking antibodies.
Project description:Pain in rheumatoid arthritis is highly debilitating, impacts quality of life and lacks adequate treatment options. Although the presence of pathogenic autoantibodies and systemic and joint inflammation are distinctive features of the disease, the molecular and neuronal basis of pain remains unclear. Here, we identify the molecular mechanism and causative neurons for autoantibody-induced pain in mice. Single-cell RNA sequencing analysis during arthritis pain revealed interferon-stimulated genes, with a persistent nociceptor neuron sensitization, local inflammation and a causative role of interferons acting on polymodal GFRa3-positive C-fiber-nociceptors, as the origin of pain. Consistently, interferon inhibition blocked gene expression alterations and prevented onset as well as reversed established and residual arthritis pain. The discovered pain-causative mechanism may represent a novel therapeutic approach for treatment of pain in rheumatoid arthritis.
Project description:To explore the biological connotation of eight syndromes of Rheumatoid Arthritis (RA) from the syndrome-symptom association network, and the relationship between the clinical characteristics of various syndromes and their key network target genes and pathways, which may offer clinicians auxiliary tools for diagnosis and treatment of RA patients with various traditional Chinese medicine (TCM) syndromes and promoting the developments of TCM Syndrome Theory. We used microarrays to detail the biological connotation of five syndromes (D-H, N) of Rheumatoid Arthritis (RA) and identified distinct classes of up-regulated and down-regulated genes during this process.
Project description:Transgenic mice with prostaglandin E2 pathway in stomach develops gastric tumors. Simultaneous activation of both Wnt pathway and prostaglandin E2 pathway causes gastric adenocarcinoma. Combination of prostaglandin E2 pathway activation and suppression of BMP pathway leads to the development of gastric hamartomas. We used microarrays to find the mechanism of these tumor development and to evaluate whether these mouse models recapitulate human gastric tumors.
Project description:Glucocorticoids are potent anti-inflammatory drugs prescribed in various diseases such as asthma, rheumatoid arthritis and multiple sclerosis. The effects of glucocorticoids have extensively been studied in immune cells. However, the regulation of inflammation by glucocorticoids in endothelial cells remains poorly understood. In this study, we stimulated murine lung endothelial cell line with dexamethasone (100 nM) and IFN-gamma (20 ng/mL) for 24 hours and extracted RNA for RNA-seq.
Project description:Genome-wide DNA methylation level was studied to determine whether Rheumatoid arthritis patients (cases) has methylation differences comparing to normal controls in PBLs. We used Illumina HumanMethylation450 BeadChip array to determine the genome-wide DNA methylation difference in PBLs from Rheumatoid arthritis patients (cases) and normal controls Bisulphite converted DNA from the Rheumatoid arthritis patients (cases) and normal controls were hybridized to the Illumina Illumina HumanMethylation450 BeadChip arrays