Project description:Xbp1 is a major transcription factor in the unfolded protein response. To uncover its function in DCs we generated a conditional KO for Xbp1 in dendritic cells. We here compare the expression of mRNAs in two different splenic DC subpopulations, CD8a and CD11b DCs in both WT and KO mice. Reference: Inositol-requiring enzyme 1-alpha regulates CD8a dendritic cell function via regulated mRNA decay. Osorio et al, Nature Immunology (2014) Primary DC subsets were isolated and sorted from spleens from 3 different WT or CD11c-cre Xbp-1fl/fl mice. RNA was isolated, converted to cDNA and then hybridised on Affymetrix GeneChip Mouse Gene 1.0 ST Arrays (GPL6246).
Project description:Analysis of the transcriptional signature of FACS-purified splenic DC subsets from Ldlr deficient mice transplanted with control or Cd11c-cre Atg16l1flox/flox bone marrow and subjected to an atherogenic diet for 8 weeks
Project description:The dendritic cell (DC)-derived chemokine CCL17, a ligand of CCR4, has been shown to promote various inflammatory diseases such as atopic dermatitis, atherosclerosis, and inflammatory bowel disease. Under steady state conditions, and even after systemic stimulation with lipopolysaccharide, CCL17 is not expressed in resident splenic DC as opposed to CD8-CD11b+ lymph node (LN) DC, which produce large amounts of CCL17, in particular after maturation. Upon systemic NKT cell activation through alpha-galactosylceramide stimulation, however, CCL17 can be upregulated in both CD8- and CD8+ splenic DC subsets and enhances cross-presentation of exogenous antigens. Based on genome wide expression profiling, we now show that splenic DC are susceptible to Interferon-gamma (IFNgamma) mediated suppression of CCL17, whereas LN DC are much less responsive to IFNgamma and downregulate the IFNgamma receptor. Under inflammatory conditions, particularly in the absence of IFNgamma signaling in IFNgamma receptor deficient mice, CCL17 expression is strongly induced in a major proportion of splenic DC by the action of granulocyte-macrophage colony stimulating factor (GM-CSF) in concert with interleukin (IL)-4. Our findings demonstrate that the local cytokine milieu and differential cytokine responsiveness of DC subsets regulate lymphoid organ specific immune responses at the level of chemokine expression. 15 h after pretreatment with 100 µg LPS, spleens and LN (MLN and PLN) from CCL17E/+ mice were harvested and DC-enriched cell suspensions of the respective organs were stained for NK1.1, CD8alpha, CD11c and CD11b. For isolation of LN DC, NK1.1-CD8alpha-CD11c+CD11b+ cells expressing CCL17/EGFP were sorted (FACSAria). Splenic DC were sorted in parallel from the same mice, but only CCL17/EGFP-negative cells expressing the same markers were selected. After the sort, cells were immediately lysed in Trizol (Invitrogen) before storage at -80°C for RNA isolation.
Project description:The dendritic cell (DC)-derived chemokine CCL17, a ligand of CCR4, has been shown to promote various inflammatory diseases such as atopic dermatitis, atherosclerosis, and inflammatory bowel disease. Under steady state conditions, and even after systemic stimulation with lipopolysaccharide, CCL17 is not expressed in resident splenic DC as opposed to CD8-CD11b+ lymph node (LN) DC, which produce large amounts of CCL17, in particular after maturation. Upon systemic NKT cell activation through alpha-galactosylceramide stimulation, however, CCL17 can be upregulated in both CD8- and CD8+ splenic DC subsets and enhances cross-presentation of exogenous antigens. Based on genome wide expression profiling, we now show that splenic DC are susceptible to Interferon-gamma (IFNgamma) mediated suppression of CCL17, whereas LN DC are much less responsive to IFNgamma and downregulate the IFNgamma receptor. Under inflammatory conditions, particularly in the absence of IFNgamma signaling in IFNgamma receptor deficient mice, CCL17 expression is strongly induced in a major proportion of splenic DC by the action of granulocyte-macrophage colony stimulating factor (GM-CSF) in concert with interleukin (IL)-4. Our findings demonstrate that the local cytokine milieu and differential cytokine responsiveness of DC subsets regulate lymphoid organ specific immune responses at the level of chemokine expression.
Project description:Dendritic cells (DCs) in tissues and lymphoid organs comprise distinct functional subsets that differentiate in situ from circulating progenitors. Tissue-specific signals that regulate DC subset differentiation are poorly understood. We report that DC-specific deletion of the Notch2 receptor caused a reduction of DC populations in the spleen. Within the splenic CD11b+ DCs, Notch signaling blockade ablated a distinct population marked by high expression of adhesion molecule Esam. The Notch-dependent Esamhi DC subset also required lymphotoxin beta receptor signaling, proliferated in situ and facilitated efficient CD4+ T cell priming. The Notch-independent Esamlo DCs expressed monocyte-related genes and showed superior cytokine responses. In addition, Notch2 deletion led to the loss of CD11b+ CD103+ DCs in the intestinal lamina propria and to the corresponding decrease of IL-17-producing CD4+ T cells in the intestine. Thus,Notch2 is a common differentiation signal for T cell-priming CD11b+ DC subsets in the spleen and intestine. We compared genome-wide expression profiles of wild-type Esam(hi) and Esam(lo) splenic CD11b+ DC populations, along with CD11b+ DCs from DC-RBPJΔ mice. Spleens from 2-3 Cx3cr1-GFP+ RBPJflox/flox CD11c-Cre+ mice or Cx3cr1-GFP+ RBPJflox/flox Cre-negative littermate controls were isolated, pooled and depleted of lymphoid and erythroid cells by negative selection on MACS columns. Live cells were stained for surface expression of CD11c, CD11b and Esam. CD11c(hi) CD11b+ DCs from control mice could be separated into Esam(lo) GFP(hi) versus Esam(hi) GFP(lo) subsets. CD11c(hi) CD11b+ DCs from RBPJ-targeted mice spleens were uniformly Esam(lo) GFP(hi). The two subsets from control mice and single Esam(lo) GFP(hi) subset from RBPJ-targeted mice were sorted using FACSAria II flow sorter and analyzed using GeneChip Mouse Gene 1.0 ST Array (Affymetrix).
Project description:Xbp1 is a major transcription factor in the unfolded protein response. To uncover its function in DCs we generated a conditional KO for Xbp1 in dendritic cells. We here compare the expression of mRNAs in two different splenic DC subpopulations, CD8a and CD11b DCs in both WT and KO mice. Reference: Inositol-requiring enzyme 1-alpha regulates CD8a dendritic cell function via regulated mRNA decay. Osorio et al, Nature Immunology (2014)
Project description:The close functional relationship between macrophages and dendritic cells has long been recognised. Here, we have examined the gene expression profiles of splenic macrophages and the splenic resident dendritic cell subsets, and demostrate that macrophages and DC show different gene expression profiles. Further, we show that the DC subsets are closer to one another in gene expression profile than they are to macrophages. We here identify a list of differentially expressed genes between the DC subsets, and between DC and macrophages Splenic macrophages, CD8+ and CD8- cDC were analyzed
Project description:The close functional relationship between macrophages and dendritic cells has long been recognised. Here, we have examined the gene expression profiles of splenic macrophages and the splenic resident dendritic cell subsets, and demostrate that macrophages and DC show different gene expression profiles. Further, we show that the DC subsets are closer to one another in gene expression profile than they are to macrophages. We here identify a list of differentially expressed genes between the DC subsets, and between DC and macrophages
Project description:The signal transducer and activator of transcription 4 (STAT4) promotes protective immunity and autoimmunity downstream of pro-inflammatory cytokines including IL-12 and IL-23. In experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis (MS), Stat4-/- mice are resistant to the development of inflammation and paralysis. Here, we examined cell-type requirements and found that in addition to T cells, STAT4 is required in dendritic cells for development of EAE. Deficiency of STAT4 in CD11c-expressing cells resulted in decreased T cell priming and inflammation in the CNS. EAE susceptibility was recovered following adoptive transfer of wild type bone marrow-derived DC to mice with STAT4-deficient DCs, but not adoptive transfer of STAT4- or IL-23R-deficient DCs. Single cell RNA-seq identified STAT4-dependent genes in DC subsets that paralleled a signature in MS patient DCs. Together, these data define a novel IL-23/DC/STAT4 pathway in DCs that could be a key to novel therapeutic targets in MS.