Project description:The impact of LPS and LTA stimulation on differentiated bone marrow and Yolk sac Hoxb8 macrophages in comparison to untreated control cells was studied by global protein profiling using a bottom-up approach.
Project description:Progenitor cells of yolk sac and bone marrow origin were transduced with an estrogen receptor Hoxb8 fusion protein to generate stable cell lines. Macrophages were differentiated with M-CSF in the absence of estrogen, and then stimulated with IL-4 or LPS. Hoxb8 progenitor cells and differentiated macrophages were analyzed by RNA sequencing.
Project description:GW182 (Tnrc6a) is a key component of RISC (miRNA-Induced Silencing Complex) that plays a critical role in miRNA-mediated gene silencing. Here, we show that GW182 is expressed in the yolk sac endoderm, and that gene-trap disruption of GW182 leads to growth arrest of yolk sac endoderm, impaired hematopoiesis and embryonic lethality. To investigate roles of GW182 in the yolk sac endoderm, we assessed changes in mRNA expression in the yolk sac of E9.5 GW182gt/gt embryos using microarrays (Affymetrix).
Project description:GW182 (Tnrc6a) is a key component of RISC (miRNA-Induced Silencing Complex) that plays a critical role in miRNA-mediated gene silencing. Here, we show that GW182 is expressed in the yolk sac endoderm, and that gene-trap disruption of GW182 leads to growth arrest of yolk sac endoderm, impaired hematopoiesis and embryonic lethality. To investigate roles of GW182 in the yolk sac endoderm, we assessed changes in mRNA expression in the yolk sac of E9.5 GW182gt/gt embryos using microarrays (Affymetrix). Yolk sac of wild type littermates and GW182gt/gt embryos at E9.5 was collected for total RNA isolation using Trizol (Invitrogen). RNAs were purified according to the manufacturer’s protocol before subjected to Mouse Gene 1.0 ST Whole Genome Array (Affymetrix) for mRNA expression profiling. Experiments were performed in triplicate. Differentially expressed mRNAs were identified using a two-sample t-test (P<0.05 considered significant).
Project description:Comparative genomic analysis of basal and LPS-induced expression patterns of bone marrow derived macrophages and bone marrow resident macrophages demonstrates completely divergent transcriptome profile and indicates/confirms the existance of two distinct monocyte/macrophage populations in murine bone marrow. Most resident tissue macrophages descent from embryonic precursors of the yolk sac but inflammatory and bone marrow (BM) macrophages are considered to develop from hematopoietic stem cells (HSCs) in the BM. We now identified a novel subpopulation of resident CD163+ macrophages in the BM which were phenotypically and functionally distinct from classical BM-derived macrophages. Bioinformatics analysis of transcriptoms indicated a unique immune-modulatory phenotype of CD163+ macrophages. Cell fate studies in Csf1rMer-iCre-Mer;RosaLSL-GFP mice demonstrated that resident CD163+ macrophages of the BM do not develop from HSCs but descent from embryonic progenitors in the yolk sac strictly dependent on transcription factor IRF8. In contrast to other yolk sac derived tissue macrophages CD163+ cells seem to play a relevant role in infections and sterile inflammation. IRF8-/- mice lacking this population are highly sensible to S. aureus infections. Thus, CD163 defines a macrophage population resident in the bone marrow but originating from yolk sac progenitors which exhibits immune-modulatory properties under different inflammatory conditions. We used quantitative RNA-seq to perform whole transcriptome analysis and compare the transcriptomes of resident CD163+ BM macrophages and classical CD163- BMDM in steady state and after LPS stimulation.
Project description:Tissue-resident macrophages can derive from yolk sac macrophages, fetal liver monocytes or adult bone marrow monocytes. Whether these precursors can give rise to transcriptionally identical alveolar macrophages is unknown. Here, we transferred traceable yolk sac macrophages, fetal liver monocytes, adult bone marrow monocytes or adult alveolar macrophages as a control, into the empty alveolar macrophage niche of neonatal Csf2rb-/- mice. All precursors efficiently colonized the alveolar niche and generated alveolar macrophages that were transcriptionally almost identical, with only 22 genes that could be linked to their origin. Underlining the physiological relevance of our findings, all transfer-derived alveolar macrophages self-maintained within the lungs for up to 1 year and durably prevented alveolar proteinosis. Thus, precursor origin does not affect the development of functional self-maintaining tissue-resident macrophages. CD45.1+CD45.2+ yolk sac macrophages, fetal liver monocytes, adult bone marrow monocytes or adult alveolar macrophages from the bronchoalveolar lavage were sorted from wild type CD45.1+CD45.2+ mice of indicated ages. From part of these samples RNA was isolated. The other part was transferred intranasally into the lungs of neonate Csf2rb-/- mice. 6 weeks post-transfer, transfer-derived CD45.1+CD45.2+ alveolar macrophages were sorted from the bronchoalveolar lavage. Wild type CD45.1+CD45.2 alveolar macrophages from the bronchoalveolar lavage of 6 week old mice were sorted as control. 36 samples (arrays) in total. RNA was isolated, amplified with Nugene pico kit, converted to cDNA and then hybridised on Affymetrix GeneChip Mouse Gene 1.0 ST Arrays.
Project description:The human yolk sac (YS) is an extra-embryonic tissue critical for early prenatal life development. It is the first site of haematopoiesis where progenitors differentiate from endoderm within blood islands of the yolk sac contributing initially to primitive erythropoiesis and in subsequent waves to erythro-myeloid and lymphoid differentiation.
Project description:The human yolk sac (YS) is an extra-embryonic tissue critical for early prenatal life development. It is the first site of haematopoiesis where progenitors differentiate from endoderm within blood islands of the yolk sac contributing initially to primitive erythropoiesis and in subsequent waves to erythro-myeloid and lymphoid differentiation.
Project description:Tissue-resident macrophages can derive from yolk sac macrophages, fetal liver monocytes or adult bone marrow monocytes. Whether these precursors can give rise to transcriptionally identical alveolar macrophages is unknown. Here, we transferred traceable yolk sac macrophages, fetal liver monocytes, adult bone marrow monocytes or adult alveolar macrophages as a control, into the empty alveolar macrophage niche of neonatal Csf2rb-/- mice. All precursors efficiently colonized the alveolar niche and generated alveolar macrophages that were transcriptionally almost identical, with only 22 genes that could be linked to their origin. Underlining the physiological relevance of our findings, all transfer-derived alveolar macrophages self-maintained within the lungs for up to 1 year and durably prevented alveolar proteinosis. Thus, precursor origin does not affect the development of functional self-maintaining tissue-resident macrophages.
Project description:Investigating the blood, immune and stromal cells present in a human fetal embryo in a world first single cell transcriptomic atlas. The embryo was dissected into 12 coronal sections, yolk sac, and yolk sac stalk. Live single cells sorted, with cell suspension then undergoing 10x chromium 5 prime scRNA-seq. This accession contains the yolk sac and yolk sac stalk data from this embryo. A matched accession contains the coronal section data. Lane "WS_wEMB12142156" (from yolk sac) was excluded from downstream analysis due to low fraction reads in cells post-CellRanger QC. Termination procedure for this embryo was medical. The F158_[features...barcodes...matrix].[tsv...mtx].gz files attached to this accession represent raw count data from all the 10x lanes in this accession combined, and as output from CellRanger filtered matrices (CellRanger version 6.0.1 using human reference genome GRCh38-2020-A). One set of count matrices relates to the yolk sac data, and one set of count matrices relates to the yolk sac stalk data.