Project description:We explored the expression profile during DC differentiation from peripheral monocytes and DC maturation induced by lipopolysaccharide (LPS).
Project description:We identify a panel of microRNAs that are differentially expressed during both spontaneous and LPS-induced DC maturation and show the M-CSF receptor (M-CSFR) as a key target for microRNA-mediated regulation. MicroRNA-22, -34a and -155 are up-regulated in mature GM-CSF-generated DC and mediate M-CSFR mRNA and protein down-regulation.
Project description:IL10-/-DC pulsed for 6h with 0, SEA, LPS, or co-pulsed with SEA/LPS together to compare changes in LPS-induced gene expression mediated by SEA (Schistosome soluble egg antigen) Keywords: other
Project description:Purpose:The purpose of this study is to detect activated or silenced genes during LPS-induced dendritic cell maturation. Gene expression differences between two samples could be found using transcriptome profiling (RNA-seq) analysis. Methods:Mouse dendritic cells were generated from bone marrow cells in RPMI-1640 medium with recombinant mouse GM-CSF and IL-4, mature DCs were obtained after LPS induced maturation. Immature DCs and mature DCs were sorted respectively based on maturation marker CD86 and Iab(MHCII) using flowcytrometer. DC mRNA profiles were generated by deep sequencing,using Illumina Results: We mapped about 10 million sequence reads per sample to the mouse genome, identified 1,300 upregulated genes and 1,475 dow regulated genes during dendritic cell maturation. DC mRNA profiles immature and mature moouse BMDCs were generated by deep sequencing
Project description:Dendritic-cell (DC) maturation involves substantial remodeling of their gene-expression program. Most research has focused on inducible gene-expression networks promoting the acquisition of new functions, such as cytokine production and enhanced T-cell-stimulatory capacity. In contrast, mechanisms that modulate DC-function by inducing gene silencing remain poorly understood. Here we describe a novel primary epigenetic-silencing response that makes major contributions to the DC-maturation process. The repressed genes function in pivotal processes - including antigen-presentation, extracellular-signal detection, signal-transduction and lipid-mediator biosynthesis - underscoring the central contribution of the silencing mechanism to rapid reshaping of DC-function. Interestingly, promoters of the repressed genes exhibit a surprisingly high frequency of PU.1-occupied sites, suggesting a novel role for this transcription factor in marking genes poised for inducible repression Analysis of PU.1 binding sites in mo-DC
Project description:Purpose:The purpose of this study is to detect activated or silenced genes during LPS-induced dendritic cell maturation. Gene expression differences between two samples could be found using transcriptome profiling (RNA-seq) analysis. Methods:Mouse dendritic cells were generated from bone marrow cells in RPMI-1640 medium with recombinant mouse GM-CSF and IL-4, mature DCs were obtained after LPS induced maturation. Immature DCs and mature DCs were sorted respectively based on maturation marker CD86 and Iab(MHCII) using flowcytrometer. DC mRNA profiles were generated by deep sequencing,using Illumina Results: We mapped about 10 million sequence reads per sample to the mouse genome, identified 1,300 upregulated genes and 1,475 dow regulated genes during dendritic cell maturation.
Project description:Cell division cycle 42 (Cdc42) is a member of the Rho GTPase family and has pivotal functions in actin organization, cell migration and proliferation. Cdc42 has been shown to regulate antigen (Ag)-uptake in immature dendritic cells (DC) and controls their migration from tissues to lymph nodes. Previous reports demonstrated that Cdc42 is inactivated upon DC-maturation to avoid continued Ag-acquisition. To further study the molecular mechanisms of DC-control by Cdc42, we used bone marrow-derived DCs from Cdc42-deficient mice. We show that Cdc42-deficient DCs are phenotypically mature without additional maturation stimuli, as they upregulate CD86 from intracellular storages to the cell surface. They also accumulate invariant chain (Ii)-MHC class II complexes at the cell surface, which cannot efficiently present peptide Ag for priming of Ag-specific CD4 T cells. Lack of Cdc42 in immature DCs does not allow MHC class II maturation, as lysosomal Cathepsins are lost into the supernatant and Ii-MHC class II complexes cannot mature. Therefore Cdc42-deficient DCs are "pseudomature" and lose most functional hallmarks of antigen-presenting cells. Our results propose that Cdc42 keeps DCs in an immature state, while downregulation of Cdc42-activity during maturation facilitates generation of CD86+MHCII+ mature DCs.
Project description:Dendritic-cell (DC) maturation involves substantial remodeling of their gene-expression program. Most research has focused on inducible gene-expression networks promoting the acquisition of new functions, such as cytokine production and enhanced T-cell-stimulatory capacity. In contrast, mechanisms that modulate DC-function by inducing gene silencing remain poorly understood. Here we describe a novel primary epigenetic-silencing response that makes major contributions to the DC-maturation process. The repressed genes function in pivotal processes - including antigen-presentation, extracellular-signal detection, signal-transduction and lipid-mediator biosynthesis - underscoring the central contribution of the silencing mechanism to rapid reshaping of DC-function. Interestingly, promoters of the repressed genes exhibit a surprisingly high frequency of PU.1-occupied sites, suggesting a novel role for this transcription factor in marking genes poised for inducible repression
Project description:Dendritic cell (DC) maturation is a prerequisite for the induction of adaptive immune responses against pathogens and cancer. Transcription factor (TF) networks control differential aspects of early DC progenitor versus late stage DC cell fate decisions. Here, we identified the TF C/EBPβ as a key regulator for DC maturation and immunogenic functionality under homeostatic and lymphoma-transformed conditions. Gene expression profiles of splenic C/EBPβ-/- DCs showed a strong downregulation of E2F cell cycle target genes, whereas signatures of maturation were enriched. In accordance with E2F1 being a negative regulator of DC maturation, C/EBPβ-/- bone marrow-derived DCs matured much faster enabling them to strongly activate T cells. Conversely, the E2F transcriptional pathways were upregulated in lymphoma-exposed DCs and DC maturation was impaired. Pharmacological blockade of C/EBPβ/mTOR signaling in human DCs abrogated their pro-tumorigenic function in B-cell lymphoma co-cultures. Thus, C/EBPβ plays a unique role in DC maturation and functionality and emerges as a key factor of the microenvironment promoting lymphomagenesis.