Project description:Dendritic cells (DCs) are comprised of a heterogenous population. Here we characterize the transcriptomic profiles of mouse splenic DC subsets at steady state to highlight key differences between subsets.
Project description:Functional characterization of human dendritic cell subsets is limited due to the very low frequency of these cells in vivo. We developed an in vitro culture system for the simultaneous generation of XCR1+ DCs and MoDCs from cord blood CD34+ cells. Their global gene expression profiles at steady state and under activation, phenotypes, morphologies and responses to different TLR ligands where characterized and compared with those of their in vivo counterparts. The study demonstrated that the XCR1+ DCs generated in vitro from cord blood CD34+ cells are equivalent to blood XCR1+ DCs and also allowed a rigorous comparison of this DC subset with MoDC which are often considered as the reference model for DCs. Altogether, our results showed that in vitro generated XCR1+ DCs are a better model for the study of blood DC than the conventionally used MoDCs. The different dendritic cell subsets used for the study were either generated in vitro from cord blood CD34+ cells with recombinant human cytokines or isolated from peripheral blood. The subsets were purified by fluorescence-activated cell sorting and their responses to PolyI:C, LPS or R848 were studied including by gene expression profiling.
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:Dendritic cells (DCs) are critical in mediating immunity to pathogens, vaccines, tumors and tolerance to self. Significant progress has been made in the study of DC subsets in murine models but the translation of these findings to human DC immunobiology has not been fully realized. Murine splenic CD8+ DC and CD103+ DC possess potent antigen cross-presenting capacity. Although recent evidence points to human blood CD141+ DCs as the functional equivalent of CD8+ DC, the precise identity of the human migratory cross-presenting DC has remained elusive. We performed phenotypic and functional analyses to interrogate the DC compartment of human non-lymphoid tissues and identified three distinct subsets: i) CD141high DCs, ii) CD1c DCs and iii) CD14+ DCs. Only CD141high DCs were capable of cross-presenting soluble antigen. Comparative transcriptome analysis of steady state monocyte and DC subsets between mouse and human confirmed conservation between species, aligning the following subsets together: i) human CD141high DCs with mouse CD8+ and CD103+ DCs, ii) human CD1c+ DCs with mouse CD4+ DCs and iii) human CD14+ DC with mouse monocyte subsets. The lack of positive association between human CD1c+ DCs and mouse non-lymphoid tissue CD11b+ DCs highlights heterogeneity and predicts the existence of a monocyte-like cell within the CD11b+ DCs. Gene expression analysis using total RNA from specific human and mouse monocyte and dendritic cell subsets purified by FACS.
Project description:Dendritic cells (DCs) are critical in mediating immunity to pathogens, vaccines, tumors and tolerance to self. Significant progress has been made in the study of DC subsets in murine models but the translation of these findings to human DC immunobiology has not been fully realized. Murine splenic CD8+ DC and CD103+ DC possess potent antigen cross-presenting capacity. Although recent evidence points to human blood CD141+ DCs as the functional equivalent of CD8+ DC, the precise identity of the human migratory cross-presenting DC has remained elusive. We performed phenotypic and functional analyses to interrogate the DC compartment of human non-lymphoid tissues and identified three distinct subsets: i) CD141high DCs, ii) CD1c DCs and iii) CD14+ DCs. Only CD141high DCs were capable of cross-presenting soluble antigen. Comparative transcriptome analysis of steady state monocyte and DC subsets between mouse and human confirmed conservation between species, aligning the following subsets together: i) human CD141high DCs with mouse CD8+ and CD103+ DCs, ii) human CD1c+ DCs with mouse CD4+ DCs and iii) human CD14+ DC with mouse monocyte subsets. The lack of positive association between human CD1c+ DCs and mouse non-lymphoid tissue CD11b+ DCs highlights heterogeneity and predicts the existence of a monocyte-like cell within the CD11b+ DCs. Gene expression analysis using total RNA from specific human and mouse monocyte and dendritic cell subsets purified by FACS.
Project description:The initiation of the mucosal immune response in Peyer’s 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.
Project description:The human bone marrow (BM) gives rise to all distinct blood cell lineages, including CD1c+ and CD141+ myeloid dendritic cells (DC) and monocytes. These cell subsets are also present in peripheral blood (PB) and lymphoid tissues. However, the difference between the BM and PB compartment in terms of differentiation state and immunological role of DC is not yet known. The BM may represent both a site for development as well as a possible effector site and so far, little is known in this light with respect to different DC subsets. Using genome-wide transcriptional profiling we found clear differences between the BM and PB compartment and a location-dependent clustering for CD1c+ and CD141+ was demonstrated. DC subsets from BM clustered together and separate from the corresponding subsets from PB, which similarly formed a cluster. In BM, a common proliferating and immature differentiating state was observed for the two DC subsets, whereas DC from the PB showed a more immune-activated mature profile. In contrast, BM-derived slan+ non-classical monocytes were closely related to their PB counterparts and not to DC subsets, implying a homogenous prolife irrespective of anatomical localization. Additional functional tests confirmed these transcriptional findings. DC-like functions were prominently exhibited by PB DC. They surpassed BM DC in maturation capacity, cytokine production and induction of CD4+ and CD8+ T cell proliferation. This first study on myeloid DC in healthy human BM offers new information on steady-state DC biology and could potentially serve as a starting point for further research on these immune cells in healthy conditions as well as in diseases.
Project description:Dendritic cell (DC) are critical initiators and regulators of immunity to pathogens, vaccines, tumors and tolerance to self. Mouse and human dendritic cells (DCs) are comprised of functionally specialized subsets, but precise interspecies correlation is currently incomplete and hampers the full translation of murine findings to human DC-based clinical therapies. In this study, we show that murine lung and gut lamina propria CD11b+ DC populations are comprised of two subsets: FLT3- and IRF4-dependent CD24+CD64- DCs and contaminating CSF-1R-dependent CD24-CD64+ macrophages. CD11b+CD24+CD64- DCs are instrumental in inducing Th17 cell immune response in the steady state and upon Aspergillus fumigatus challenge. We also identified human CD1c+CD11b+ DCs as the functional homologue of mouse mucosal CD11b+ DCs. Our findings highlight the conservation of key immune functions across species and aid the translation of murine studies to human DC immunobiology. The data for the associated human studies have been stored within GSE35459. Gene Expression from total RNA from specific mouse dendritic cell subsets purified by FACS
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.
Project description:Dendritic cells (DCs) are critical in mediating immunity to pathogens, vaccines, tumors and tolerance to self. Significant progress has been made in the study of DC subsets in murine models but the translation of these findings to human DC immunobiology has not been fully realized. Murine splenic CD8+ DC and CD103+ DC possess potent antigen cross-presenting capacity. Although recent evidence points to human blood CD141+ DCs as the functional equivalent of CD8+ DC, the precise identity of the human migratory cross-presenting DC has remained elusive. We performed phenotypic and functional analyses to interrogate the DC compartment of human non-lymphoid tissues and identified three distinct subsets: i) CD141high DCs, ii) CD1c DCs and iii) CD14+ DCs. Only CD141high DCs were capable of cross-presenting soluble antigen. Comparative transcriptome analysis of steady state monocyte and DC subsets between mouse and human confirmed conservation between species, aligning the following subsets together: i) human CD141high DCs with mouse CD8+ and CD103+ DCs, ii) human CD1c+ DCs with mouse CD4+ DCs and iii) human CD14+ DC with mouse monocyte subsets. The lack of positive association between human CD1c+ DCs and mouse non-lymphoid tissue CD11b+ DCs highlights heterogeneity and predicts the existence of a monocyte-like cell within the CD11b+ DCs.