Functional characterization of human dendritic cell subsets is limited due to the very low frequency of these cells in vivo. We developed an in vitro culture system for the simultaneous generation of XCR1+ DCs and MoDCs from cord blood CD34+ cells. Their global gene expression profiles at steady state and under activation, phenotypes, morphologies and responses to different TLR ligands where characterized and compared with those of their in vivo counterparts. The study demonstrated that the XCR1+ DCs generated in vitro from cord blood CD34+ cells are equivalent to blood XCR1+ DCs and also allowed a rigorous comparison of this DC subset with MoDC which are often considered as the reference model for DCs. Altogether, our results showed that in vitro generated XCR1+ DCs are a better model for the study of blood DC than the conventionally used MoDCs.
Human XCR1+ dendritic cells derived in vitro from CD34+ progenitors closely resemble blood dendritic cells, including their adjuvant responsiveness, contrary to monocyte-derived dendritic cells.
Specimen part, Treatment
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Broad and Largely Concordant Molecular Changes Characterize Tolerogenic and Immunogenic Dendritic Cell Maturation in Thymus and Periphery.
Specimen part, Treatment
View SamplesPsoriasis is a chronic inflammatory skin disease of unknown etiology. Although macrophages and dendritic cells (DCs) have been proposed to drive the psoriatic cascade, their largely overlapping phenotype hampered studying their respective role. Topical application of Imiquimod, a Toll-like receptor 7 agonist, induces psoriasis in patients and psoriasiform inflammation in mice. We showed that daily application of Imiquimod for 14 days recapitulated both the initiation and the maintenance phase of psoriasis. Based on our ability to discriminate Langerhans cells (LCs), conventional DCs, monocytes, monocyte-derived DCs and macrophages in the skin, we characterized their dynamics during both phases of psoriasis. During the initiation phase, neutrophils infiltrated the epidermis whereas monocytes and monocyte-derived DCs were predominant in the dermis. During the maintenance phase, LCs and macrophage numbers increased in the epidermis and dermis, respectively. LC expansion resulted from local proliferation, a conclusion supported by transcriptional analysis. Continuous depletion of LCs during the course of Imiquimod treatment aggravated chronic psoriatic symptoms as documented by an increased influx of neutrophils and a stronger inflammation. Therefore, by developing a mouse model that mimics the human disease more accurately, we established that LCs play a negative regulatory role during the maintenance phase of psoriasis.
Dynamics and Transcriptomics of Skin Dendritic Cells and Macrophages in an Imiquimod-Induced, Biphasic Mouse Model of Psoriasis.
Specimen part, Treatment
View SamplesPlasmacytoid dendritic cells (pDC) are the major source of type I interferons (IFN-I) during viral infections, in response to triggering of endosomal Toll Like Receptors (TLR) 7 or 9 by viral single-stranded RNA or unmethylated CpG DNA, respectively. IFN-I production in pDC occurs in specialized endosomes encompassing preformed signaling complexes of TLR7 or 9 with their adaptor molecule MyD88 and the transcription factor interferon regulatory factor 7 (IRF7). The triggering of TLR leads to IRF7 phosphorylation, nuclear translocation and binding to the promoters of the genes encoding IFN-I to initiate their transcription. pDC express uniquely high levels of IRF7 at steady state and this expression is further enhanced by positive IFN-I feedback signaling during viral infections. However, the specific cell-intrinsic roles of MyD88 versus IFN-I signaling in pDC responses to a viral infection have not been rigorously dissected. To achieve this aim, we generated mixed bone marrow chimera mice (MBMC) allowing to rigorously compare the gene expression profiles of WT versus Ifnar1-KO or MyD88-KO pDC isolated from the same animals at steady state or after infection with the mouse cytomegalovirus (MCMV). Our results indicate that, in vivo during MCMV infection, pDC undergo a major transcriptional reprogramming, under combined instruction of IFN-I, IFN- and direct TLR triggering. However, these different stimuli drive specific, largely distinct, gene expression programs. We rigorously determined which gene modules require cell-intrinsic IFN-I signaling for their induction in pDC during a physiological viral infection in vivo. We delineated non-redundant versus shared versus antagonistic responses with IFN-. We demonstrated that cell-intrinsic IFN-I responsiveness is dispensable for induction of the expression of all IFN-I/III genes and many cytokines or chemokines in pDC during MCMV infection, contrary to MyD88 signaling.
Molecular dissection of plasmacytoid dendritic cell activation <i>in vivo</i> during a viral infection.
Specimen part, Treatment
View SamplesMurine Cytomegalovirus (MCMV) infection leads to early activation of various immune cells, including B and T lymphocytes, before the actual initiation of antigen-specific adaptive immunity. This activation is partly driven by innate cytokines, including type I interferon (IFN), which are induced early after infection. The objective of this study was to address the role of type I IFN in shaping early/innate B and T cell responses to a primary acute viral infection.
Plasmacytoid, conventional, and monocyte-derived dendritic cells undergo a profound and convergent genetic reprogramming during their maturation.
Specimen part
View SamplesMurine Cytomegalovirus (MCMV) infection leads to the activation of various immune cells, including dendritic cells (DCs) and Natural Killer (NK) cells. This activation is partly driven by innate cytokines including IFN-I, which are induced early after infection. The objective was to address the role of different innate cytokines in shaping DC subsets and NK cell responses, in particular the role of cell intrinsic responses to IFN-I.
Differential responses of immune cells to type I interferon contribute to host resistance to viral infection.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Active STAT5 regulates T-bet and eomesodermin expression in CD8 T cells and imprints a T-bet-dependent Tc1 program with repressed IL-6/TGF-β1 signaling.
Specimen part
View SamplesThis series contains re-analyzed samples from GSE39555, GSE39556 and GSE15907.
Broad and Largely Concordant Molecular Changes Characterize Tolerogenic and Immunogenic Dendritic Cell Maturation in Thymus and Periphery.
Specimen part
View SamplesTranscriptome analyses of naive, effector and memory CD8 TCRP1A lymphocytes expressing or not an active form of the transcription factor Stat5.
Active STAT5 regulates T-bet and eomesodermin expression in CD8 T cells and imprints a T-bet-dependent Tc1 program with repressed IL-6/TGF-β1 signaling.
Specimen part
View SamplesBlood genomic profiling has been applied to disorders of the blood and various organ systems including brain to elucidate disease mechanisms and identify surrogate disease markers. Since most studies have not examined specific cell types, we performed a preliminary genomic survey of major blood cell types from normal individuals using microarrays. CD4+ T cells, CD8+ T cells, CD19+ B cells, CD56+ natural killer cells, and CD14+ monocytes were negatively selected using the RosetteSep antibody cocktail, while polymorphonuclear leukocytes were separated with density gradient media.
Genomic profiles for human peripheral blood T cells, B cells, natural killer cells, monocytes, and polymorphonuclear cells: comparisons to ischemic stroke, migraine, and Tourette syndrome.
Specimen part, Disease
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