Project description:In mice, two restricted DC progenitors, macrophage-dendritic progenitor (MDP) and common dendritic cell progenitor (CDP) demonstrate increasing commitment of DC lineage as they sequentially lose granulocyte and monocyte potential respectively. Identifying these progenitors has enabled understanding of the role of DCs and monocytes in immunity and tolerance in mice. In humans, however, restricted monocyte and DC progenitors remain unknown. Progress in studying human DC development has been hampered by lack of an in vitro culture system that recapitulates in vivo DC hematopoiesis. Here we report a culture system that supports development of CD34+ hematopoietic stem cell progenitors into the three major human DC subsets, monocytes, granulocytes, NK and B cells. Using this culture system we defined the pathway for human DC development, and revealed the sequential origin of human DCs from increasingly restricted progenitors: a granulocyte-monocyte-DC progenitor (hGMDP) that develops into a monocyte-DC progenitor (hMDP) that develops into monocytes and a common DC progenitor (hCDP) that is restricted to produce the three major DC subsets. The phenotype of the DC progenitors partially overlaps with granulocyte monocyte progenitors (GMPs). These progenitors reside in human cord blood and bone marrow but not in the blood or lymphoid tissues in the steady state. We performed whole transcriptome expression analysis on monocytes and subsets of dendritic cells i.e. CD1c+ DCs, CD141+ DCs and CD303+ pDCs isolated from blood or differentiated in culture from cord blood CD34+ cells in presence of MS5 stromal cells and Flt3l, GM-CSF and SCF cytokines.
Project description: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
Project description:Monocytes can give rise to multiple highly specialized cell types to perform a wide array of functions, ranging from pathogen phagocytosis to bone resorption. This differentiation is induced by the binding of cytokines to dedicated receptors on the surface of monocytes, which results in the initiation of genetic programs that enable cells to perform their specialized functions. Given their common background, it is not surprising that monocyte-derived cells share abilities and cellular markers, yet their specialized functions require a dedicated set of proteins. In order to dissect the monocyte differentiation process and to define cell type-specific marker proteins, we differentiated circulating monocytes into dendritic cells, M1 and M2 macrophages, and osteoclasts, and assessed their proteomes by quantitative mass spectrometry throughout the differentiation process. Statistical analysis indicated that monocyte differentiation is a linear process characterized by a common core of proteins that is similarly affected among the distinct differentiation paths. Throughout the specialization process a cluster of RNA-binding and processing proteins was downregulated whereas proteins associated to metabolic processes were increased. Analysis of the specialized cells after 10 days of differentiation uncovered existing and putative novel dendritic cell markers. Combined, we here present a comprehensive proteomic analysis of monocyte differentiation uncovering shared and distinct proteomic features of differentiating monocytes and monocyte-derived cells.
Project description:Monocytes cultured in media containing GM-CSF and IL4 for 5 days normally differentiate into immature dendritic cells which, upon further stimulation with LPS for an additional 2 days, acquire a mature phenotype. In the present study, we evaluated the effect of human cord-blood mesenchymal stem cells (MSC) on human monocyte differentiation into immature and mature DCs by examining the trancriptional profile of the cells that were obtained after both the differentiation and maturation stages.
Project description:As supplies of monocytes, macrophages and dendritic cells from human sources can be scarce or prone to donor variation we established an efficient method to generate induced pluripotent stem cell derived monocytes that in turn could be differentiated into both macrophages and dendritic cells. We used RNA sequencing to profile these from multiple differentiation runs (n=3) and multiple monocyte harvests (n=3-4) and compared them to their blood derived counterparts, blood derived monocyte, monocyte derived macrophages and moncyte derived dendritic cells (from 3 donors).
Project description:We have carried out global gene expression analysis to clarify the interrelationship between 1,25-dihydroxyvitamin D3 and differentiation-driven gene expression patterns in developing human monocyte-derived dendritic cells. Monocytes were treated with 10 nM 1,25-dihydroxyvitamin D3 or vehicle 14 hours after plating for 12 hours or 5 days. Monocytes, differentiating dendritic cells (+/-1,25-dihydroxyvitamin D3 for 12 hours) and immature dendritic cells (+/-1,25-dihydroxyvitamin D3 for 5 days) were harvested. This design allows one to identify genes regulated by differentiation and/or 1,25-dihydroxyvitamin D3 in human monocyte-derived dendritic cells.