Murine 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 SamplesPlasmacytoid dendritic cells wre isolated from cutaneous lymph nodes of control C57BL/6 mice and used for microarray analysis.
Comparative genomics analysis of mononuclear phagocyte subsets confirms homology between lymphoid tissue-resident and dermal XCR1(+) DCs in mouse and human and distinguishes them from Langerhans cells.
Specimen part
View SamplesTranscriptome analysis of five population of Antigen Presenting Cells: inflammatory macrophages, Inflammatory dendritic cells, Cd14+CD16- monocytes, CD14 dim Cd16+ monocytes and BDCA1+ Dendritic cells.
Human inflammatory dendritic cells induce Th17 cell differentiation.
No sample metadata fields
View SamplesCD34+ cord blood hematopoietic progenitors were expanded in vitro as previously described (Balan et al., J Immunol, 2014) and then differentiated on a mixed feeder layer of OP9 cells expressing or not the Notch ligand Delta-like 1, with FLT3-L, TPO and IL-7. At the end of the cultures, single live Lin- HLA-DR+ cells were index sorted in 96-well plates containing lysis buffer, and snap frozen. Four putative cell types were sorted according to their expression patterns of key combinations of cell surface markers: putative pDCs, putative cDC1s, putative pre-cDC2s and putative cDC2s. Single cell RNA-sequencing libraries were subsequently generated for 90 single cells and 6 control wells using an adaptation of Smart-Seq2 (Villani et al., Science, 2017). Cells were sequenced at a depth of 1-3M reads/cell. Overall design: A total of 90 single cells and 6 controls from one culture were processed using a protocol adapted from Smart-Seq2 protocol (Villani et al., Science, 2017), which allows for the generation of full-length single cell cDNA, and sequencing libraries were generated using Illumina Nextera XT DNA library preparation kit. A few samples (10) were profiled but excluded from the processed data since they were either bulk (5) or blank (1) control samples or excluded due to QC (4). Therefore, there are 86 samples included here.
Large-Scale Human Dendritic Cell Differentiation Revealing Notch-Dependent Lineage Bifurcation and Heterogeneity.
Specimen part, Subject
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 SamplesThe initiation of the mucosal immune response in Peyers patch (PP) relies on the sampling, processing and efficient presentation of foreign antigens by dendritic cells (DC). PP DC encompass five subsets, among which CD11b+ conventional DC (cDC) and LysoDC have distinct progenitors and functions but share many cell surface markers. This has previously led to confusion between these two subsets. In addition, another PP DC subset, termed double-negative (DN), remains poorly characterized. Here, we have studied the genetic relatedness of the different subsets of PP cDC at steady state and under TLR7 ligand stimulation. We also provide the transcriptional profiles of subepithelial TIM-4- and interfollicular TIM-4+ macrophages.
Distribution, location, and transcriptional profile of Peyer's patch conventional DC subsets at steady state and under TLR7 ligand stimulation.
Sex, Age, Specimen part, Treatment
View SamplesFor both PBMC and cells from the in vitro cultures, RNA purification and library generation was performed using the Chromium Single Cell Controller apparatus and associated protocols (10X Genomics). Libraries were sequenced by 75-bp single-end reading on a NextSeq500 sequencer (Illumina). Reads were aligned on the GRCh38 human genome assembly. Data analysis was performed using the R software package Seurat (https://github.com/satijalab/seurat) Overall design: Single cell RNA-seq data were generated on the 10X emulsion platform (10X Genomics, Pleasanton, CA) according to the manufacturer's instructions. NextSeq data from the Chromium platform were processed using CellRanger v1.3.1, and subsequent normalization, QC, filtering, and differential gene expression analysis was performed in R using Seurat v1.4.0.16.
Large-Scale Human Dendritic Cell Differentiation Revealing Notch-Dependent Lineage Bifurcation and Heterogeneity.
Specimen part, Subject
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 SamplesThe goal of this experiment was to use global gene expression profiling to assess the global genetic reprogramming of different types of splenic mononuclear phagocytes early after MCMV infection in vivo. This study includes new samples (GSM3178486-GSM3178497; available below) profiling splenic CD11b+ conventional dendritic cells (cDC2), classical monocytes (cMo) and red pulp macrophages (RPM) from untreated or day 1.5 MCMV-infected mice together with re-analysis of previously published data in order to examine the similarities in the pDC gene expression profiles across datasets.
Molecular dissection of plasmacytoid dendritic cell activation <i>in vivo</i> during a viral infection.
Specimen part, Treatment
View SamplesDendritic cells (DC) are the most potent antigen-presenting cells of the immune system. In lymph nodes (LN), they are also believed to dispose of apoptotic cells, a critical function usually achieved by macrophages (M) in other tissues. We report a population of tolerogenic M located in the T cell zone of LN. T zone M (TZM) are long lived M seeded after birth and slowly replaced by blood monocytes. We show that TZM but not DC act as the only professional scavengers clearing apoptotic cells in the LN T cell zone. Importantly, we demonstrate that TZM prevent the capture of apoptotic cells by DC and the associated potential noxious activation of T cell immunity. We thus propose a new model in which efferocytosis and T cell activation are uncoupled processes handled by TZM and DC respectively.
T Cell Zone Resident Macrophages Silently Dispose of Apoptotic Cells in the Lymph Node.
Specimen part
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