Project description:Primary mouse bone marrow mesenchymal stromal cells (BM-MSCs) cultured for bone differentiation were exposed to vehicle (DMSO), synthetic RXR ligand (LG100268), type 2 diabetes therapeutic and PPARγ ligand (Rosiglitazone), and environmental PPARγ ligands (Tributyltin, Triphenyl Phosphate, and MEHP) to evaluate differential gene expression as well as nuclear receptor expression and downstream PPARG target gene expression between all chemical exposures
Project description:In bone marrow (BM), there are two different types of stem/progenitor cells. With respect to hematopoiesis, hematopoietic stem/progenitor cells (HPCs) produce mature blood cells and mesenchymal stromal/stem cells (MSCs) support this. The influence of exposure to low-dose radiation on human HPCs has been investigated, and generation of both immature and mature hematopoietic cells from human HPCs is compromised. On the other hand, the influence of exposure to low-dose radiation on MSCs is not known. This gene expression profiling was created for investigation how low-dose irradiation affects BM-MSCs genomically.
Project description:RNA-seq of human BM-derived mesenchymal stromal cells (MSCs) cocultured with mouse BM cells upon GM-CSF stimulation against MSCs without BM cell coculture
Project description:Bone marrow-derived multipotent stromal cells (BM-MSCs) exhibit therapuetically valuable properties, including the capacity to differentiate into skeletal tissues and modulate immune system activity. These properties depend on proper regulation of dynamic gene expression in response to environmental and developmental stimuli. This study used chromatin immunoprecipitation (ChIP) coupled with human promoter tiling microarray analysis (ChIP-on-chip) to profile histones H3K4me3 and H3K27me3 at promoters genome-wide. The goal of the study was to identify gene promoters marked by H3K27me3 and H3K4me3 in BM-MSCs.
Project description:BRD4, a member of the BET family of histone readers, binds to acetylated lysine of histone H3 and promotes assembly of super-enhancer complexes that drive expression of key oncogenes in acute myeloid leukemia (AML) and other cancers. ARV-825 is a proteolysis-targeting chimera (PROTAC) that targets BRD4 for CRBN-mediated ubiquitination and degradation. BM-MSCs are an important element of the bone marrow microenvironment of AML. To understand how targeting BRD4 in BM-MSCs may contribute to the overall effect on AML of targeting BRD4, we treated BM-MSCs from two normal donors with ARV-825 in vitro. Treatment of BM-MSC monocultures with ARV-825 for 24 hr caused extensive changes in gene expression, highly uniform between triplicates. Although the cultures from the two normal donors showed different profiles, their changes with ARV-825 were highly similar. These changes implicated effects on oxidative stress, osteogenic differentiation, retinoid metabolism, F-actin polymerization, CXCL12, and proliferation.
Project description:We set out to study the effects of the endocrine disrupting chemical tributyltin (TBT) on early lineage commitment of primary bone marrow-derived mesenchymal stem cells (MSCs) from the long bones of C57BL/6 mice. We previously showed that prenatal exposure to nanomolar levels of TBT results in increased adiposity in mice. TBT is an agonist of two nuclear receptors, peroxisome proliferator-activated receptor gamma (PPARγ) and retinoid X receptor (RXR), master regulators of adipogenesis. To test if TBT could influence early MSC lineage commitment we treated these cells with 50 nM TBT, 100 nM Rosiglitazone (ROSI, a pure PPARγ agonist), 100 nM AGN194204 (4204, a pure RXR agonist), and vehicle control (0.1% DMSO) for 48 hours prior to differentiation with a standard adipogenic cocktail. This experiment revealed an RXR-dependent commitment to the adipose lineage. To better understand how TBT induces adipose commimtment, we sequenced RNA from MSCs treated with DMSO (0.1%), ROSI (100 nM), 4204 (100 nM), and TBT (50 nM) for 48 hrs, prior to any differentiation. Unbiased hierarchical clustering analysis showed a clear separation between DMSO and ROSI replicates from 4204 and TBT, strengthening our conclusion that the observed phentype is RXR-dependent. Pathway analysis of differentially expressed genes revealed that TBT and 4204 de-repress targets of the repressive histone modifier Enhancer of zeste 2 (EZH2), the catalytic member of the Polycomb repressive complex 2 (PRC2), which deposits H3K27me3 on histones. We there for preformed ChIP-Seq analysis on MSCs treated with DMSO (0.1%) or TBT (50 nM) for 48 hrs, hypothesizing that TBT would reduce H3K27me3 in proximity to genes that regulate adipose lineage commitment.
Project description:Bone marrow-derived multipotent stromal cells (BM-MSCs) exhibit therapuetically valuable properties, including the capacity to differentiate into skeletal tissues and modulate immune system activity. These properties depend on proper regulation of dynamic gene expression in response to environmental and developmental stimuli. This study used chromatin immunoprecipitation (ChIP) coupled with human promoter tiling microarray analysis (ChIP-on-chip) to profile histones H3K4me3 and H3K27me3 at promoters genome-wide. The goal of the study was to identify gene promoters marked by H3K27me3 and H3K4me3 in BM-MSCs. ChIP-on-chip performed with antibodies to H3K4me3 and H3K27me3 on BM-MSCs from 3 different donors (labeled 1632, 167696, and 8F3560) and with technical replicates.
Project description:The bone marrow (BM) niche regulates multiple HSC processes. Clinical treatment for hematological malignancies, by HSC transplantation often requires preconditioning total body irradiation, which severely and irreversibly impairs the BM niche and HSC regeneration. Novel strategies to enhance HSC regeneration in irradiated BM are needed. We compared the effects of niche factors EGF, FGF2 and PDGFB on HSC hematopoietic regeneration using human MSCs that were transduced with these factors via lentiviral vectors. Among above niche factors tested, PDGFB-MSCs most significantly improved human hematopoietic cell engraftment in immunodeficient mice. PDGFB-MSC-treated BM more efficiently enhanced transplanted human HSC self-renewal in secondary transplantations from primary recipients. Although PDGFB-MSCs did not directly increase HSC expansion in vitro, GSEA revealed anti-apoptotic signaling being increased in PDGFB-MSCs versus GFP-MSCs. PDGFB-MSCs had enhanced survival and expansion after transplantation, leading to an enlarged humanized niche cell pool. Our study demonstrates the efficacy of MSC-mediated niche factors in clinical HSC transplantation for patients.