Project description:Transcriptomic profiling (RNA-seq) of the four most primitive human stem and progenitor populations. Purpose: to compare the transcriptomic profile of the four most primitive human stem and progenitor populations (all are CD34+CD38-CD45RA-): CD90+CD49f+, CD90-CD49f+, CD90+CD49f-, CD90-CD49f-. Conclusions: previouls study of gene expression analysis of these populations were performed using microarray hence, this study represents the first analysis of transcriptomes from these populations generated by RNA-seq technology. The optimized data analysis workflows reported here should provide a framework for comparative investigations of expression profiles of other human blood stem/progenitor populations.
Project description:Gene expression studies from hematopoietic stem cell (HSC) populations purified to variable degrees have defined a set of stemness genes. The present study describes the construction and comparative molecular analysis of l-phage cDNA libraries from highly purified primitive HSCs (PHSCs) which retained their long term repopulating activities (LTRAs), and from maturing HSCs (MHSCs) which were largely depleted of LTRAs. Library inserts were amplified and tagged by a T7 RNA polymerase promoter and used to generate biotinylated cRNA for Microarray hybridization. Microarray analysis of the libraries confirmed previous results but also revealed an unforseen preferential expression of translation and metabolism associated genes in the PHSCs. Therefore these data indicate that HSCs are quiescent only in regard of proliferative activities, but are in a state of readiness to provide the metabolic and translational activities required following induction of proliferation by factors which induce differentiation and exit from the HSC pool. We used microarrays to detail the global programme of gene expression distinguishing primitive and maturing hematopoietic stem cells from mouse bone marrow and identified distinct classes of up- and down-regulated genes. Experiment Overall Design: To compare the transcriptosomes of primitive and maturing hematopoietic stem cells from mouse bone marrow, cDNA libraries were generated from RNA isolated from highly purified stem cell populations and used to generate biotinylated cRNA for Affymetrix microarray analysis.
Project description:Single cell transcriptomic profiling (sc RNA-seq) of the most primitive Human Hematopoietic Stem Cell Population described: CD34+CD38-CD45RA-CD49f+EPCR+ (hereafter EPCR+).
Project description:Purpose: to compare the transcriptomic profile of the two most primitive human EPCR+ stem and CD90+EPCR- progenitor populations. Methods: cells were obtained from human cord-blood and flow-sorted using the surface antigens described. 5 EPCR+ and 4 CD90+EPCR- biological replicates were used to extract total RNA and quality was verified (RIN >8). Libraries were prepared using with 20-25 ng/sample of starting RNA. All samples were sequenced two independent times. Conclusions: this study represents the first analysis of transcriptomes from the two most primitive human stem/progenitor populations, with biologic replicates, generated by RNA-seq technology. The optimized data analysis workflows reported here should provide a framework for comparative investigations of expression profiles of other human blood stem/progenitor populations.
Project description:Gene expression studies from hematopoietic stem cell (HSC) populations purified to variable degrees have defined a set of stemness genes. The present study describes the construction and comparative molecular analysis of l-phage cDNA libraries from highly purified primitive HSCs (PHSCs) which retained their long term repopulating activities (LTRAs), and from maturing HSCs (MHSCs) which were largely depleted of LTRAs. Library inserts were amplified and tagged by a T7 RNA polymerase promoter and used to generate biotinylated cRNA for Microarray hybridization. Microarray analysis of the libraries confirmed previous results but also revealed an unforseen preferential expression of translation and metabolism associated genes in the PHSCs. Therefore these data indicate that HSCs are quiescent only in regard of proliferative activities, but are in a state of readiness to provide the metabolic and translational activities required following induction of proliferation by factors which induce differentiation and exit from the HSC pool. We used microarrays to detail the global programme of gene expression distinguishing primitive and maturing hematopoietic stem cells from mouse bone marrow and identified distinct classes of up- and down-regulated genes. Keywords: Adult hematopoietic stem cell populations
Project description:Human embryonic stem cells (hESCs) offer an important model for investigating the human hematopoietic celldevelopment. Here, we used long serial analysis of gene expression and quantitative real-time PCR to characterize two subsets of primitive hematopoietic cells derived in vitro from hESCs. This revealed differences in their expression of genes associated with lymphoid and myeloid development, cellular biosynthetic processes, and cell cycle regulation. Further comparisons with analogous data for primitive hematopoietic cells isolated from first trimester human fetal liver and newborn cord blood showed a strong similarity between the transcriptomes of the most primitive hESC- and in vivo-derived populations, with the main differences involving genes that regulate HSC development, self-renewal and homing, chromatin remodeling, AP1 transcription complex genes, and non-coding RNAs. These data suggest that primitive hematopoietic cells are generated from hESCs in vitro by processes similar to those operative during human embryogenesis in vivo, although some differences were also detected. Human embryonic stem cells (hESCs) are capable of indefinite self-renewal but can also be induced to undergo a stepwise process of differentiation into a spectrum of recognizable mature blood cell types. However, a clear understanding of the molecular mechanism by which the first hematopoietic stem cells (HSCs) acquire their unique defining properties of self-renewal and repopulating potential is lacking. As a first step towards obtaining the information needed to close this gap, we have undertaken a comparative gene expression analysis of different highly purified primitive human hematopoietic subpopulations (erythroid-megakaryocytic progenitor enriched CD43+CD235a+CD41a+/- cells, mutiplepotent progenitor enriched lin-CD34+CD43+CD45-, and lin-CD34+CD43+CD45+ cells) generated either in vitro from hESCs or in vivo from fetal (human fetal liver lin-CD34+CD38- cells) or neonatal hematopoietic primitive cells (human cord blood lin-CD34+CD38- and lin-CD34+CD38+ cells). This involved preparing a long serial analysis of gene expression (LongSAGE) library from an extracts of each prospectively isolated subpopulation and then sequencing each library to a depth of 200,000 tags.