Gene expression profile of GM-CSF derived bone marrow dendritic cell subsets after LPS stimulation
ABSTRACT: GM-CSF derived bone marrow cultures contain several subsets of CD11c+MHCII+ mononuclear phagocytes Using Affymetrix microarrays we compared gene expression of the different mononuclear phagocytes within the bone marrow culture. The different populations are left unstimulated or are stimulated with LPS The Affymetrix GeneChip Mouse Gene 1.0 arrays were used to define gene expression profiles in the different population.
Project description:GM-CSF derived bone marrow cultures contain several subsets of CD11c+MHCII+ mononuclear phagocytes Using Affymetrix microarrays we compared gene expression of the different mononuclear phagocytes within the bone marrow culture. The different populations are left unstimulated or are stimulated with LPS The Affymetrix GeneChip Mouse Gene 1.0 arrays were used to define gene expression profiles in the different population.
Project description:GM-CSF derived bone marrow cultures contain several subsets of CD11c+MHCII+ mononuclear phagocytes Using Affymetrix microarrays we compared gene expression of the different mononuclear phagocytes within the bone marrow culture The Affymetrix GeneChip Mouse Gene 1.0 arrays were used to define gene expression profiles in the different population.
Project description:Microarray experiments were performed to compare the gene expression profiles exhibited by immature and activated bone-marrow (BM) derived conventional DCs (BM-cDCs) and plasmacytoid DCs (BM-pDCs) from WT and miR155-/- mice. (time points 0, 4 and 24 hours)
Project description:Dendritic cells (DCs) are the most potent antigen (Ag)-presenting cells. Whereas immature DCs down-regulate T cell responses to induce/maintain immunological tolerance, mature DCs promote immunity. To amplify their functions, DCs communicate with neighboring DCs through soluble mediators, cell-to-cell contact and vesicle exchange. Transfer of nanovesicles (<100nm) derived from the endocytic pathway (termed exosomes) represents a novel mechanism of DC-to-DC communication. The facts that exosomes contain exosome-shuttle microRNAs (miRNAs), and DC functions can be regulated by exogenous miRNAs, suggest that DC-to-DC interactions could be mediated through exosome-shuttle miRNAs, an hypothesis that remains to be tested. Importantly, the mechanism of transfer of exosome-shuttle miRNAs from the exosome lumen to the cytosol of target cells is unknown. Here, we demonstrate that DCs release exosomes with different miRNAs depending on the maturation of the DCs. By visualizing spontaneous transfer of exosomes between DCs, we demonstrate that exosomes fused with the target DCs, the latter followed by release of the exosome content into the DC cytosol. Importantly, exosome-shuttle miRNAs are functional, as they repress target mRNAs of acceptor DCs. Our findings unveil a mechanism of transfer of exosome-shuttle miRNAs between DCs and its role as a means of communication and post-transcriptional regulation between DCs. The study has analyzed the microRNA content of 4 samples of immature exosomes, 4 samples of matures exosomes, 2 samples of immature bone-marrow-derived DCs, and 2 samples of mature bone marrow-derived DCs.
Project description:We have previously demonstrated that bone marrow-derived DC can prevent diabetes development and halt progression of insulitis in NOD mice, the mouse model of type 1 diabetes (T1D). The DC population that was most effective in this therapy had a mature phenotype, expressed high levels of costimulatory molecules and secreted low levels of IL-12p70. The protective DC therapy induced regulatory Th2 cells that shifted the dominant Th1 environment, present in NOD mice, to a mixed Th1/Th2 milieu. Microarray analysis of therapeutic and non-therapeutic DC populations revealed several novel molecules that could play important roles in the observed DC-mediated therapy. The therapeutic DC population expressed a unique pattern of costimulatory molecules and chemokines, which were confirmed by flow cytometry and ELISA assays. We have performed in vitro chemotaxis assays that demonstrated the therapeutic DC preferentially attracted Th2 cells, as compared to Th1, Treg or naïve T cells. In addition we quantified the in vivo migration of activated islet-specific T cells to the pancreas using novel cell labeling techniques and 19F nuclear magnetic resonance. A subcutaenous injection of therapeutic DC alters the migration of both Th1 and Th2 cells to the pancreas, and Th1 cells appeared in the lymph node draining the site of DC injection. These results suggest that the therapeutic function of DC is mediated in part by the chemoattractive properties of these DC for diabetogenic Th1 cells. Bone marrow cells from NOD mice were cultured in GM or GM + IL-4 to generate DC. DC were purified on metrizamide gradients after 4 days of culture. Purified DC were stimulated with LPS + IFNg and RNA taken 0, 6 and 20 hours after stimulation. Three biological replicates were performed but not all RNA samples were good. The are 3 replicates for GM/0, GM4/0, GM4/6 and 2 replicates for GM/6, GM/20 and GM4/20
Project description:Innate stimulation with TLR ligands leads to the activation of various genes in macrophages and various populations of these cells may exhibit different responses. Here wanted to delineate and characterize these transcriptional responses in newly established, self-renewing, in vitro grown non-transformed lines (MPI cells) and bone marrow derived macrophages We used microarrays to detail the global programme of gene expression Newly synthesized RNA from independently established MPI lines and bone marrow derived macrophages was extracted and hybridized to Affymetrix microarrays
Project description:Granulocyte-Macrophage colony stimulating factor (GM-CSF) devlops heterogenous myeloid cell populations from bone marrow progenitor cells. In vitro generated bone marrow derived cells are excellent sources for obtaining dendritic cells or macrophages, but it is still not clear about the exact mixed population characteristics of GM-CSF grown cells. We revealed here that GM-CSF grown bone marrow cell derived attaching cells were composed of dendritic cells (GM-BMDC) as well as macrophages (GM-BMM). We compared the transcriptome profiles of these cell populations as well as M-CSF grown bone marrow derived macrophages (M-BMM). We used microarrays to detail the global profile of gene expressions between three populations of CSF-grown bone marrow derived cells: GM-CSF derived dendritic cells (GM-BMDC), GM-CSF derived macrophages (GM-BMM) and M-CSF derived macrophages (M-BMM). Bone marrow cells were differentiated for 7 days with 25 ng/ml GM-CSF or 20% L cell conditioned media as a M-CSF supplier. GM-BMDCs were sorted from MHCIIhighF4/80low population and GM-BMMs were sorted in the MHCIIlowF4/80high population. M-BMMs were sorted from CD11b+F4/80+ population.
Project description:Analysis of genes induced in DC precursors and in BM cells and monocytes treated with GM-CSF For progenitor arrays, bone marrow progenitors (CMP, GMP, CDP, and pre-cDC) were harvested from WT C57Bl/6 mice. For culture arrays, BM was cultured in the presence of GM-CSF or M-CSF and adherent and non-adherent cells sorted. For monocyte cultures, sorted BM monocytes were treated with GM-CSF for 0, 24 or 48 hours.