Project description:Understanding how cellular function is imprinted during development requires the identification of factors controlling lineage specification and commitment, and the intermediate progenitors in which they act. Using population level and single cell approaches, we examine transcriptional and functional heterogeneity within early innate lymphoid cells (ILC) progenitors. We identify a developmental bifurcation toward dendritic cell fate that reveals the uncommitted state of early specified ILC progenitors. We subsequently characterize an ILC-commitment checkpoint controlled by the transcription factor TCF-1. The present study reveals unexpected heterogeneity within early innate progenitor populations, and characterizes lineage infidelity that accompanies early ILC specification prior to commitment.
Project description:Understanding how cellular function is imprinted during development requires the identification of factors controlling lineage specification and commitment, and the intermediate progenitors in which they act. Using population level and single cell approaches, we examine transcriptional and functional heterogeneity within early innate lymphoid cells (ILC) progenitors. We identify a developmental bifurcation toward dendritic cell fate that reveals the uncommitted state of early specified ILC progenitors. We subsequently characterize an ILC-commitment checkpoint controlled by the transcription factor TCF-1. The present study reveals unexpected heterogeneity within early innate progenitor populations, and characterizes lineage infidelity that accompanies early ILC specification prior to commitment.
Project description:This SuperSeries is composed of the following subset Series: GSE34892: IRF-8 extinguishes neutrophil production and promotes dendritic cell lineage commitment in both myeloid and lymphoid progenitors (Affymetrix). GSE34915: IRF-8 extinguishes neutrophil production and promotes dendritic cell lineage commitment in both myeloid and lymphoid progenitors (Illumina). Refer to individual Series
Project description:Single cell-based studies have revealed tremendous cellular heterogeneity in stem cell and progenitor compartments, suggesting continuous differentiation trajectories with intermixing of cells at various states of lineage commitment and notable degree of plasticity during organogenesis. The hepato-pancreato-biliary organ system relies on a small endoderm progenitor compartment that gives rise to a variety of different adult tissues, including liver, pancreas, gallbladder, and extra-hepatic bile ducts. Experimental manipulation of various developmental signals in the mouse embryo underscored important cellular plasticity in this embryonic territory. This is also reflected in the existence of human genetic syndromes as well as congenital or environmentally-caused human malformations featuring multiorgan phenotypes in liver, pancreas and gallbladder. Nevertheless, the precise lineage hierarchy and succession of events leading to the segregation of an endoderm progenitor compartment into hepatic, biliary, and pancreatic structures are not yet established. Here, we combine computational modelling approaches with genetic lineage tracing to assess the tissue dynamics accompanying the ontogeny of the hepato-pancreato-biliary organ system. We show that a multipotent progenitor domain persists at the border between liver and pancreas, even after pancreatic fate is specified, contributing to the formation of several organ derivatives, including the liver. Moreover, using single-cell RNA sequencing we define a specialized niche that possibly supports such extended cell fate plasticity.
Project description:Haematopoietic stem cells (HSC) and multipotent progenitor cells (MPP) generate all cells of the blood system, although cellular heterogeneity and bias in lineage potential have been observed. Here, we examined whether lineage-specific transcription factors, such as the B-lineage determinant EBF1, establish lineage bias in early progenitors. We detect low level EBF1 expression in myeloid-biased MPP3 and lymphoid-biased MPP4 cells, and show that Ebf1-deficient animals display reduced HSC quiescence and repopulation capacity, enhanced myelopoiesis and enhanced myeloid differentiation potential of MPP3 and MPP4 cells. Bulk and single-cell RNA-seq analysis revealed a CEBPa-driven myeloid transcriptome in Ebf1-deficient progenitors, and we find that EBF1 binds and potentially antagonizes the haematopoietic Cebpa enhancer. In MPP3 cells, EBF1 additionally primes enhancers associated with B-lymphoid genes that gain expression in common lymphoid progenitors. Thus, our study identifies EBF1 as an important determinant in regulating the balance of myeloid versus lymphoid potential in the earliest hematopoietic progenitors.
Project description:Haematopoietic stem cells (HSC) and multipotent progenitor cells (MPP) generate all cells of the blood system, although cellular heterogeneity and bias in lineage potential have been observed. Here, we examined whether lineage-specific transcription factors, such as the B-lineage determinant EBF1, establish lineage bias in early progenitors. We detect low level EBF1 expression in myeloid-biased MPP3 and lymphoid-biased MPP4 cells, and show that Ebf1-deficient animals display reduced HSC quiescence and repopulation capacity, enhanced myelopoiesis and enhanced myeloid differentiation potential of MPP3 and MPP4 cells. Bulk and single-cell RNA-seq analysis revealed a CEBPa-driven myeloid transcriptome in Ebf1-deficient progenitors, and we find that EBF1 binds and potentially antagonizes the haematopoietic Cebpa enhancer. In MPP3 cells, EBF1 additionally primes enhancers associated with B-lymphoid genes that gain expression in common lymphoid progenitors. Thus, our study identifies EBF1 as an important determinant in regulating the balance of myeloid versus lymphoid potential in the earliest hematopoietic progenitors.
Project description:Haematopoietic stem cells (HSC) and multipotent progenitor cells (MPP) generate all cells of the blood system, although cellular heterogeneity and bias in lineage potential have been observed. Here, we examined whether lineage-specific transcription factors, such as the B-lineage determinant EBF1, establish lineage bias in early progenitors. We detect low level EBF1 expression in myeloid-biased MPP3 and lymphoid-biased MPP4 cells, and show that Ebf1-deficient animals display reduced HSC quiescence and repopulation capacity, enhanced myelopoiesis and enhanced myeloid differentiation potential of MPP3 and MPP4 cells. Bulk and single-cell RNA-seq analysis revealed a CEBPa-driven myeloid transcriptome in Ebf1-deficient progenitors, and we find that EBF1 binds and potentially antagonizes the haematopoietic Cebpa enhancer. In MPP3 cells, EBF1 additionally primes enhancers associated with B-lymphoid genes that gain expression in common lymphoid progenitors. Thus, our study identifies EBF1 as an important determinant in regulating the balance of myeloid versus lymphoid potential in the earliest hematopoietic progenitors.