Project description:The 70% resection promotes migration of Ly6C+CD11b+ monocytes/macrophages to the remnant liver accompanied by a reduction in its CD206+ macrophage content. mRNA and microRNA expression profiles were studied by NanoString technology and verified by a reverse transcription-based qPCR assay. Corresponding microtranscriptomic profiles cannot be unambiguously defined as pro- or anti-inflammatory. Their typical features include elevated expression of leukocyte chemoattractant factors, and many of the differentially expressed sequences are related to the control of cell growth and metabolic processes in the liver.
Project description:As a rule, mammalian organs contain a mixed population of macrophages from different sources of origin. It is assumed that the self-sustaining resident macrophages and the monocyte-derived transient macrophages differ by their functional properties and their roles in repair processes . The analysis of the functional features of different populations of macrophages is of significant practical importance, since macrophages are considered as therapeutic targets in various pathological conditions and as prospective basis for cell therapy products. The aim of this study was to compare microRNA profiles of the two alternative macrophage species exemplified, respectively, by Kupffer cells of the liver and monocytes of the blood.
Project description:To incorporate Kupffer cells into hiPSC-LOs, we differentiated erythro-myeloid progenitors (EMPs) from hiPSCs. We compares the gene expression profiles of hiPSC-EMPs with cord-blood hematopoietic stem and progenitor cells (CB-HSPCs); and EMP-generated Kupffer cells (EMP-KC) with human primary Kupffer cells.
Project description:Self-renewing tissue-resident macrophages are thought to be exclusively derived from embryonic progenitors. However, whether circulating monocytes can also give rise to such macrophages has not been formally investigated. Here we use a new model of diphtheria toxin-mediated depletion of liver-resident Kupffer cells to generate niche availability and show that circulating monocytes engrafted in the liver, gradually adopt the transcriptional profile of their depleted counterparts and become long-lived self-renewing cells. Underlining the physiological relevance of our findings, circulating monocytes also contribute to the expanding pool of macrophages in the liver shortly after birth, when macrophage niches become available during normal organ growth. Thus, like embryonic precursors, monocytes can and do give rise to self-renewing tissue-resident macrophages if the niche is available to them. Clec4F+ Kupffer cells were isolated and sorted from livers from adult WT mice or KC-DTR or KC-DTR littermate control mice +/- 50ng DT at indicated timepoints. 19 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:Kupffer cells (KCs) are the tissue resident macrophage population of the liver. With this experiment, we sought to investigate the potential consequences of decreasing embryonically-derived KC numbers on liver gene expression in the context of hypercholesterolemia. 3-month-old CD207-DTR x LDL-receptor deficient (C57BL6J background) female mice were injected with diphtheria toxin (DT) or heat-inactivated DT. Mice were then fed a cholesterol-rich diet to induce hypercholesterolemia. RNA sequencing was performed on liver RNA samples after 4 weeks of diet.
Project description:Molecular profiling of infiltrating monocyte-derived macrophages versus resident kupffer cells following acute liver injury The liver has a remarkable capacity to regenerate after injury; yet, the role of macrophages (MF) in this process remains controversial mainly due to difficulties in distinguishing between different MF-subsets. Here, we utilized a murine model of acute liver injury caused by overdose of acetaminophen (APAP) and defined three distinct MF subsets that populate the liver following injury. Accordingly, resident Kupffer cells (KC) were significantly reduced upon APAP-challenge and started recovering by self-renewal at resolution phase without contribution of circulating Ly6Chi monocytes. The latter were recruited in a CCR2 and M-CSF mediated pathway at the necro-inflammatory phase and differentiated into ephemeral Ly6Clo MF subset at resolution phase. Moreover, their inducible ablation resulted in impaired recovery. Microarray based molecular profiling uncovered high similarity between steady state KC and those recovered at the resolution phase. In contrast, KC and monocyte-derived MF displayed distinct pro-restorative genetic signature at the resolution phase. Finally, we show that infiltrating monocytes acquire a pro-restorative polarization manifested by unique expression of pro-angiogenesis mediators and genes involved with inhibition of neutrophil activity and recruitment and promotion of their clearance. Collectively, our results present a novel phenotypic, ontogenic and molecular definition of liver-MF compartment following acute injury. 11 Samples (arrays) were performed. We generated pairwise comparison between all the different macrophages stages, using Partek Genomics Suite. Genes with p?5%[FDR] and a fold-change difference of ?2 or <-2 were selected.