Project description:Single cell RNA sequencing-based comparison of mouse splenic pDC, pDC-like cells, tDC, cDC1 and cDC2 at steady state and during a viral infection
Project description:Plasmacytoid dendritic cells (pDC) are the main source of type I interferon (IFN) during viral infections. Their other functions are debated, due to a lack of tools to identify and target them in vivo without affecting pDC-like cells and transitional DC (tDC), which harbor overlapping phenotypes and transcriptomes but a higher efficacy for T cell activation. To overcome this bottleneck, we designed, generated and validated a pDC-Tomato reporter mouse. We bred pDC-Tomato with Zbtb46 GFP mice to yield the he ZeST mouse strain that enabled transcriptomic profiling of all splenic DC types, by single cell RNA sequencing, both at steady state and during the course of the infection with mouse cytomegalovirus (MCMV). Analyses of the transcriptomic dataset unraveled diverging activation of pDC-like cells vs tDC during the infection. This dataset and the associated specific gene modules will be useful to delineate the physiological functions of pDC versus other DC types.
Project description:Conventional dendritic cells (cDC) consist of two functionally and phenotypically distinct subsets, cDC1 and cDC2, whose development is dependent on distinct sets of transcription factors. Interferon regulatory factor 8 (IRF8) is required at multiple stages of cDC1 development, but its role in mature cDC1 remains unclear. Here we used XCR1-cre to delete Irf8 in committed cDC1 and demonstrate that Irf8 is required for maintaining the identify of cDC1 but not their survival. In the absence of Irf8, committed cDC1 (“ex-cDC1”) acquired the transcriptional, functional and chromatin accessibility properties of cDC2. This conversion was independent on Irf4 and was associated with decreased accessibility in putative IRF8, Batf3 and composite AP-1-IRF (AICE) binding elements, together with increased accessibility of cDC2 associated transcription factor binding elements. Thus, IRF8 expression by committed cDC1 is required for preventing their conversion into cDC2.
Project description:Expression data from cDC2 derived from in vitro culture from Batf3 KO pre-cDC1 and IRF8 +32 KO pre-cDC1 compared to cDC1 derived from in vitro culture of WT pre-cDC1 or cDC2 derived from in vitro culture of WT pre-cDC2
Project description:The transcriptomes of primary isolated unstimulated murine splenic cDC1 and cDC2 from specific pathogen free (SPF) were compared to cDC1 and cDC2 from Germ Free (GF) and Interferon alpha/beta receptor 1 (Ifnar) knock out mice. Total RNA was prepared from sort-purified cDC1 and cDC2 (for each sample 3 individual mice were pooled) using Trizol reagent (Invitrogen) in combination with the miRNeasy Micro Kit (Qiagen) according to the manufacturer’s instructions. For poly-A-dependent cDNA synthesis and a first amplification step 10 ng of total RNA was used as input in the Smart-Seq v4 mRNA Ultra Low Input RNA Kit (Clontech) and processed according to the manufacturer’s instructions. 1 ng of the purified cDNA was used for tagmentation and library completion with the Nextera XT library preparation kit (Illumina). In the following, 2x75nt paired-end sequencing was performed on a NextSeq 500.
Project description:The spleen contains phenotypically and functionally distinct cDC1 and cDC2 subpopulations, which each can be divided into several smaller and less-well characterized subsets. Despite advances in understanding the complexity of DC ontogeny and function by transcriptional programming, the significance of post-translational modifications in controlling tissue-specific cDC (subset) immunobiology remains elusive. Here, we identified the cell surface-expressed A-disintegrin-and-metalloproteinase 10 (ADAM10) as an essential regulator of cDC1 and cDC2 homeostasis in the splenic marginal zone (MZ). Mice with a CD11c-specific deletion of ADAM10 (ADAM10ΔCD11c) exhibited a complete loss of splenic ESAMhi cDC2A, because ADAM10 controlled their commitment, differentiation, survival, and EBI2-mediated localization within the MZ. Moreover, we discovered that ADAM10 is a molecular switch regulating cDC2 subset heterogeneity in the spleen, as this unbalanced cDC2A homeostasis in the absence of ADAM10 was compensated for by the emergence of a novel Clec12a+ cDC2B subset, closely resembling cDC2 generally found in peripheral lymph nodes. Moreover, in ADAM10ΔCD11c mice terminal differentiation of cDC1 was abrogated, resulting in reduced numbers of Langerin+ cDC1.
Project description:The spleen contains phenotypically and functionally distinct cDC1 and cDC2 subpopulations, which each can be divided into several smaller and less-well characterized subsets. Despite advances in understanding the complexity of DC ontogeny and function by transcriptional programming, the significance of post-translational modifications in controlling tissue-specific cDC (subset) immunobiology remains elusive. Here, we identified the cell surface-expressed A-disintegrin-and-metalloproteinase 10 (ADAM10) as an essential regulator of cDC1 and cDC2 homeostasis in the splenic marginal zone (MZ). Mice with a CD11c-specific deletion of ADAM10 (ADAM10ΔCD11c) exhibited a complete loss of splenic ESAMhi cDC2A, because ADAM10 controlled their commitment, differentiation, survival, and EBI2-mediated localization within the MZ. Moreover, we discovered that ADAM10 is a molecular switch regulating cDC2 subset heterogeneity in the spleen, as this unbalanced cDC2A homeostasis in the absence of ADAM10 was compensated for by the emergence of a novel Clec12a+ cDC2B subset, closely resembling cDC2 generally found in peripheral lymph nodes. Moreover, in ADAM10ΔCD11c mice terminal differentiation of cDC1 was abrogated, resulting in reduced numbers of Langerin+ cDC1.