Project description:This is part of a larger experiment in which the effects of IL-13, LIGHT and TGF-B1 on human primary esophageal fibroblasts were analyzed and compared.
Project description:Primary myelofibrosis (PMF) is a myeloproliferative neoplasm characterized by clonal expansion of myeloid cells, notably megakaryocytes (MKs), and aberrant cytokine production leading to bone marrow (BM) fibrosis and insufficiency. Current treatment options are limited. TGF-b1, a profibrotic and immunosuppressive cytokine, is involved in PMF pathogenesis. While all cell types secrete inactive, latent TGF-b1, only a few activate the cytokine via cell type-specific mechanisms. The cellular source of the active TGF-b1 implicated in PMF is not known. Transmembrane protein GARP binds and activates latent TGF-b1 on the surface of regulatory T lymphocytes (Tregs) and MKs or platelets. Here, we found increased expression of GARP in BM and spleen of mice undergoing PMF and tested the therapeutic potential of a monoclonal antibody that blocks TGF-b1 activation by GARP-expressing cells. GARP:TGF-b1 blockade reduced not only fibrosis, but also clonal expansion of transformed cells. Using mice carrying a genetic deletion of Garp in either Tregs or MKs, we found that the therapeutic effects of GARP:TGF-b1 blockade in PMF imply targeting GARP on Tregs. These therapeutic effects, accompanied by increased IFN-g signals in the spleen, were lost upon CD8 T cell depletion. Our results suggest that selective blockade of TGF-b1 activation by GARP-expressing Tregs increase a CD8 T cell-mediated immune reaction that limits transformed cell expansion, providing a novel approach that could be tested to treat patients with myeloproliferative neoplasms.
Project description:Response of mouse mammary epithelial cells NMuMG to TGF-b1 - time course experiment. Identification of novel gene targets involved in TGF-b1-driven regulation of epithelial-mesenchymal transition (EMT).
Project description:Regulation of organismal homeostasis in response to nutrient availability is a vital physiological process that involves inter-organ communication. Understanding the mechanisms controlling systemic cross talk for maintenance of metabolic health is critical to counteract diet-induced obesity. Here, we show that cardiac-derived transforming growth factor beta 1 (TGF-b1) protects against weight gain and glucose intolerance in mice subjected to high-fat diet. Secretion of TGF-b1 by cardiomyocytes correlates with bioavailability of this factor in circulation. TGF-b1 prevents adipose tissue inflammation independent of body weight and glucose metabolism phenotypes, suggesting protection from adipocyte dysfunction-driven immune cell recruitment. TGF-b1 alters gene expression programs in white adipocytes, favoring their thermogenic fate and consequently increasing their mitochondrial oxygen consumption rates. Ultimately, subcutaneous and visceral white adipose tissue from heart-specific TGF-b1 transgenic mice fail to undergo cellular hypertrophy, leading to reduced overall adiposity during high-fat feeding. Thus, TGF-b1 is a critical mediator of heart-fat communication for regulation of systemic metabolism.
Project description:Long-term peritoneal dialysis is associated with progressive fibrosis of the peritoneum. Epithelial-mesenchymal transition (EMT) of mesothelial cells is an important mechanism involved in peritoneal fibrosis, and TGF-b1 is considered central in this process. We conducted network-based integrated analysis of transcriptomic data to systemically characterize the molecular signature of TGF-b1-stimulated human peritoneal mesothelial cells (HPMCs).
Project description:Pluripotent stem cells have been shown to have unique nuclear properties, e.g., hyperdynamic chromatin and large, condensed nucleoli. However, the contribution of the latter unique nucleolar character to pluripotency has not been well understood. Here, we show fibrillarin (FBL), a critical methyltransferase for ribosomal RNA (rRNA) processing in nucleoli, as one of the proteins highly expressed in pluripotent embryonic stem (ES) cells. Stable expression of FBL in ES cells prolonged the pluripotent state of mouse ES cells cultured in the absence of leukemia inhibitory factor (LIF). Analyses using deletion mutants and a point mutant revealed that the methyltransferase activity of FBL regulates stem cell pluripotency. Knock down of this gene led to significant delays in rRNA processing, growth inhibition, and apoptosis in mouse ES cells. Interestingly, both partial knock down of FBL and treatment with actinomycin D, an inhibitor for rRNA synthesis, induced the expression of differentiation markers in the presence of LIF and promoted stem cell differentiation into neuronal lineages. Moreover, we identified p53 signaling as the regulatory pathway for pluripotency and differentiation of ES cells. These results suggest that proper activity of rRNA production in nucleoli is a novel factor for the regulation of pluripotency and differentiation ability of ES cells. Tc-inducible FBL-knock down ES cells were cultured for 2 days with or without Tc in the presence of LIF. These 2 conditions were analysed transcription profile.
Project description:EMT is a developmental process, which can be reactivated in cancer cells. Cancer cells maintaining EMT in the circulation may have pro-metastatic properties. We used microarrays to profile EMT-related gene expression changes after 14 d of TGF-b1 treatment. EpRas cells were cultured in standard conditions either in the presence of absence of recombinant TGF-b1 (2 ng/ml) for 14 d. After this period, RNA was isolated from triplicate wells of treated and non-treated cells, and hybridized on Affymetrix microarrays.
Project description:Isolated primary human fibroblasts from 5 control and 5 IPF patients were treated with/out 3ng/ml TGF-b1 for 24 hours before cells were lysed for RNA extraction.