Project description:These data show that the genes that distinguish myofibroblasts from fibroblasts are myriad, and that some genes not traditionally associated with myofibroblast differentiation may serve as novel therapeutic targets for fibrosing disorders. Gene expression levels were assessed from total RNA on the Affymetrix U219 microarray. Here, we use transforming growth factor-β1 (TGF-β1) and prostaglandin E2 (PGE2), which has recently been shown to reverse myofibroblast differentiation, to investigate the transcriptomic changes that occur during TGF-β1-induced differentiation and PGE2-induced de-differentiation of myofibroblasts.
Project description:Fibrotic diseases have significant health impact and have been associated with differentiation of the resident fibroblasts into myofibroblasts. In particular, stiffened extracellular matrix and TGF-β1 in fibrotic lesions have been shown to promote pathogenic myofibroblast activation and progression of fibrosis in various tissues. To better understand the roles of mechanical and chemical cues on myofibroblast differentiation and how they may crosstalk, we cultured primary valvular interstitial cells (VICs) isolated from porcine aortic valves and studied how traditional TCPS culture, which presents a non-physiologically stiff environment, and TGF-β1 affect native VIC phenotypes. We carried out gene expression profiling using porcine genome microarrays from Affymetrix and found that traditional TCPS culture induces major changes in gene expression of native VICs, rendering these cells more activated and similar to cells treated with TGF-β1. We also monitored time-dependent effects induced by TGF-β1 by examining gene expression changes induced by TGF-β1 at 8 hours and 24 hours. Porcine aortic VICs were isolated and cultured with or without TGF-β1 treatment for RNA extraction and hybridization on Affymetrix microarrays. We included 3 biological replicates for each condition. P0 VICs were freshly isolated cells which had not been cultured. P2 VICs were cells that had been passaged 2 times and cultured on plastic plates in low serum media. Some of the P2 VICs were treated with TGF-β1 at 5ng/ml for 8 hours or 24 hours. All the control and TGF-β1-treated conditions were collected at the same time on day 3 of culture.
Project description:Bronchiolitis obliterans (BO) is a pulmonary chronic graft-versus-host disease (cGVHD), which is a noninfectious, irreversible, and poor prognostic complication after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Fibroblast-myofibroblast transition (FMT)-derived myofibroblasts (MFB) are the main effector cells involved in the development of BO. Through multiple regulations, the anti-fibrotic potential of mesenchymal stem cells (MSC) has been widely studied and was implied with potential clinical value. However, the MSC-mediated regulation of FMT and underlying mechanisms remained largely undefined. By identifying TGF-β1 hypertension as the pivotal landmark during the profibrotic FMT, TGF-β1-induced MFB and uMSC co-culture models were established and utilized to investigate regulations by uMSC on FMT in vitro. Methods including RNA sequencing (RNA-seq), Western blot, qPCR and flow cytometry were used. Our results revealed that uMSC reversibly dedifferentiated MFB into a group of FB-like cells by modulating the TGF-β-SMAD2/3 signaling. Importantly, these proliferation-boosted FB-like cells remained sensitive to TGF-β1 and could be re-induced into MFB. Our findings highlighted the reversibility of uMSC-mediated inhibitions on FMT through TGF-β-SMAD2/3 signaling, which may explain MSC's inconsistent clinical efficacies in treating BO and other fibrotic diseases. These dedifferentiated FB-like cells are still sensitive to TGF-β1 and may further deteriorate MFB phenotypes unless the profibrotic environment is corrected.
Project description:Tissue inhibitor of metalloproteinase 1 (TIMP-1) controls matrix metalloproteinase (MMP) activity through 1:1 stochiometric binding. Human TIMP-1 fused to a glycosylphosphatidylinositol (GPI) anchor (TIMP-1-GPI) shifts the activity of TIMP-1 from the extracellular matrix to the cell surface. TIMP-1-GPI treated renal cell carcinoma cells (RCC) show increased apoptosis and reduced proliferation. Transcriptomic profiling and regulatory pathway mapping were used to identify potential mechanisms driving these effects. Significant changes in inhibitor of DNA binding (IDs), TGF-β1/SMAD and BMP pathways resulted from TIMP-1-GPI treatment. These events were linked to reduced TGF-β1 signaling mediated by inhibition of proteolytic processing of latent TGF-β1 by TIMP-1-GPI. Activity of TIMP-1 from the extracellular matrix to the cell surface. TIMP-1-GPI treated renal cell carcinoma cells (RCC) show increased apoptosis and reduced proliferation. Transcriptomic profiling and regulatory pathway mapping were used to identify potential mechanisms driving these effects. Significant changes in inhibitor of DNA binding (IDs), TGF-β1/SMAD and BMP pathways resulted from TIMP-1-GPI treatment. These events were linked to reduced TGF-β1 signaling mediated by inhibition of proteolytic processing of latent TGF-β1 by TIMP-1-GPI. Renal cell carcinoma cells were transfected with empty vector, rhTimp1 and 2 concentrations of Timp1-GPI fusion protein
Project description:Fibrotic diseases have significant health impact and have been associated with differentiation of the resident fibroblasts into myofibroblasts. In particular, stiffened extracellular matrix and TGF-β1 in fibrotic lesions have been shown to promote pathogenic myofibroblast activation and progression of fibrosis in various tissues. To better understand the roles of mechanical and chemical cues on myofibroblast differentiation and how they may crosstalk, we cultured primary valvular interstitial cells (VICs) isolated from porcine aortic valves and studied how traditional TCPS culture, which presents a non-physiologically stiff environment, and TGF-β1 affect native VIC phenotypes. We carried out gene expression profiling using porcine genome microarrays from Affymetrix and found that traditional TCPS culture induces major changes in gene expression of native VICs, rendering these cells more activated and similar to cells treated with TGF-β1. We also monitored time-dependent effects induced by TGF-β1 by examining gene expression changes induced by TGF-β1 at 8 hours and 24 hours.
Project description:Members of the NADPH oxidase (NOX) family of enzymes, which catalyze the reduction of O2 to reactive oxygen species, have increased in number during eukaryotic evolution. Seven isoforms of the NOX gene family have been identified in mammals; however, specific roles of NOX enzymes in mammalian physiology and pathophysiology have not been fully elucidated. The best established physiological role of NOX enzymes is in host defense against pathogen invasion in diverse species, including plants. The prototypical member of this family, NOX-2 (gp91phox), is expressed in phagocytic cells and mediates microbicidal activities. Here we report a role for the NOX4 isoform in tissue repair functions of myofibroblasts and fibrogenesis. Transforming growth factor-β1 (TGF-β1) induces NOX-4 expression in lung mesenchymal cells by a SMAD-3–dependent mechanism. NOX-4–dependent generation of hydrogen peroxide (H2O2) is required for TGF-β1–induced myofibroblast differentiation, extracellular matrix (ECM) production and contractility. NOX-4 is upregulated in lungs of mice subjected to noninfectious injury and in cases of human idiopathic pulmonary fibrosis (IPF). Genetic or pharmacologic targeting of NOX-4 abrogates fibrogenesis in two murine models of lung injury. These studies support a function for NOX4 in tissue fibrogenesis and provide proof of concept for therapeutic targeting of NOX-4 in recalcitrant fibrotic disorders. Experiment Overall Design: mRNA expression of genes in human fetal lung mesenchymal cells (IMR-90) treated with or without TGF-β1, as analyzed by Affymetrix (U133A) microarrays. Control (C0, C2, C3) = cells without TGF-β1 treatment (n=3). Experimental (T0, T5, T7) = cells treated with TGF-β1 (2ng/ml) (n=3). mRNA was collected for all 6 samples for 48 hours post treatment.
Project description:We report a novel licensing strategy to improve the immunosuppressive capacity of MSCs. Licensing murine MSCs with TGF-β1 (TGF-β MSC) significantly improved their ability to modulate both the phenotype and secretome of inflammatory bone marrow-derived macrophages and significantly increased the numbers of regulatory T lymphocytes (Tregs) following co-culture assays. These TGF-β MSC-expanded Tregs also expressed significantly higher levels of PD-L1 and CD73, indicating enhanced suppressive potential. Detailed analysis of T lymphocyte co-cultures revealed modulation of secreted factors, most notably, elevated prostaglandin E2 (PGE2). Furthermore, TGF-β MSCs could significantly prolong rejection-free survival (69.2% acceptance rate compared to 21.4% for un-licensed MSC treated recipients) in a murine corneal allograft model. Mechanistic studies revealed that (i) therapeutic efficacy of TGF-β MSCs is Smad2/3-dependent; (ii) TGF-β MSC’s enhanced immunosuppressive capacity is contact-dependent and (iii) enhanced secretion of PGE2 (via prostaglandin EP4 receptor) by TGF-β MSCs is the predominant mediator of Treg expansion and T cell activation and is associated with corneal allograft survival. Collectively, we provide compelling evidence for the use of TGF-β1 licensing as an unconventional strategy for enhancing MSC immunosuppressive capacity.
Project description:Background: Myofibroblasts (MYFs) are generally considered the principal culprits in excessive extracellular matrix deposition and scar formation in the pathogenesis of lung fibrosis. Lipofibroblasts (LIFs), on the other hand, are defined by their lipid-storing capacity and are predominantly found in the alveolar regions of the lung. They have been proposed to play a protective role in lung fibrosis. We previously reported that a LIF to MYF reversible differentiation switch occurred during fibrosis formation and resolution. In this study, we tested whether WI-38 cells, a human embryonic lung fibroblast cell line, could be used to study fibroblast differentiation towards the LIF or MYF phenotype and whether this could be relevant for idiopathic pulmonary fibrosis (IPF). Methods: using WI-38 cells, MYF differentiation was triggered using TGF-β1 treatment and LIF differentiation using Metformin treatment. We analyzed the LIF to MYF and MYF to LIF differentiation by pre-treating the WI-38 cells with TGF-β1 or Metformin first, followed by treatment with Metformin and TGF-β1, respectively. We used IF, qPCR and bulk RNA-Seq to analyze the phenotypic and transcriptomic changes in the cells. We correlated our in vitro transcriptome data from WI-38 cells (obtained via bulk RNA sequencing) with the transcriptomic signature of LIFs and MYFs derived from the IPF cell atlas as well as with our own single-cell transcriptomic data from IFP patients-derived lung fibroblasts (LF-IPF) cultured in vitro. We also carried out alveolosphere assays to evaluate the ability of the proposed LIF and MYF cells to support the growth of alveolar epithelial type 2 cells. Results: WI-38 and LF-IPF display similar phenotypical and gene expression responses to TGF-β1 and Metformin treatment. Bulk RNA-Seq analysis of WI-38 and LF-IPF treated with TGF-β1, or Metformin indicate similar transcriptomic changes. We also show the partial conservation of the LIF and MYF signature extracted from the Habermann et al. scRNA-seq dataset in WI-38 cells treated with Metformin or TGF-β1, respectively. Alveolosphere assays indicate that LIFs enhance organoid growth, while MYFs inhibit organoid growth. Finally, we provide evidence supporting the LIF to MYF reversible switch using WI-38 cells. Conclusions: WI-38 cells represent a versatile and reliable model to study the intricate dynamics of fibroblast differentiation towards the MYF or LIF phenotype associated with lung fibrosis formation and resolution, providing valuable insights to drive future research
Project description:Tissue inhibitor of metalloproteinase 1 (TIMP-1) controls matrix metalloproteinase (MMP) activity through 1:1 stochiometric binding. Human TIMP-1 fused to a glycosylphosphatidylinositol (GPI) anchor (TIMP-1-GPI) shifts the activity of TIMP-1 from the extracellular matrix to the cell surface. TIMP-1-GPI treated renal cell carcinoma cells (RCC) show increased apoptosis and reduced proliferation. Transcriptomic profiling and regulatory pathway mapping were used to identify potential mechanisms driving these effects. Significant changes in inhibitor of DNA binding (IDs), TGF-β1/SMAD and BMP pathways resulted from TIMP-1-GPI treatment. These events were linked to reduced TGF-β1 signaling mediated by inhibition of proteolytic processing of latent TGF-β1 by TIMP-1-GPI. Activity of TIMP-1 from the extracellular matrix to the cell surface. TIMP-1-GPI treated renal cell carcinoma cells (RCC) show increased apoptosis and reduced proliferation. Transcriptomic profiling and regulatory pathway mapping were used to identify potential mechanisms driving these effects. Significant changes in inhibitor of DNA binding (IDs), TGF-β1/SMAD and BMP pathways resulted from TIMP-1-GPI treatment. These events were linked to reduced TGF-β1 signaling mediated by inhibition of proteolytic processing of latent TGF-β1 by TIMP-1-GPI.
Project description:Transcriptomic analyses were conducted to discover potential mechanisms of TGF-β1-induced changes in MSCs and the effect of MDSC supernatant treatment.