Project description:IRF2, IRF6, and MYB are candidate regulators of human erythropoiesis. We here examine primary CD34+ hematopoietic stem/progenitor cells (HSPCs)-derived erythroid progenitors with control, IRF2, IRF6, or MYB shRNA lentiviral transduction prior to differentiation. Gene expression microarray profiling datasets for MYB shRNA and control shRNA were obtained from Gene Expression Omnibus (GEO) under accession number GSE25678. The data were analyzed together with the datasets obtained in this study. Primary maturing adult erythroblasts were generated ex vivo from CD34+ hematopoietic stem/progenitor cells (HSPCs) using a serum-free two-phase liquid culture system. CD34+ HSPCs were transduced with lentiviruses containing shRNAs against IRF2 or IRF6 gene, selected and differentiated to proerythroblasts (ProEs). Cells were harvested at day 5 of differentiated and total RNA were extracted. This was used to hybridize to Affymetrix expression arrays using the HG-U133 Plus 2.0 platform.
Project description:The supply of red blood cells (RBCs) is not sufficient in many developing countries or in developed countries for patients who need chronic transfusion from best-matched donors. Ex vivo expansion and maturation of human erythroid precursor cells (erythroblasts) could represent a potential solution. Proliferating erythroblasts can be expanded from human umbilical cord blood mononuclear cells (CB MNCs) ex vivo for 10^6-10^7 fold (in ~50 days) before undergoing senescence. Here, we report that ectopic expression of three to four genetic factors that have been used for iPS cell derivation enables CB-derived erythroblasts to undergo extended ex vivo expansion (M-bM-^IM-%10^51 fold in ~9 months) in a defined suspension culture condition without change of cell identity or function. These vastly expanding erythroblasts maintain homogeneously immature erythroblast phenotypes, a normal diploid karyotype and dependence on specific combination of cytokines and hormone for survival and proliferation throughout the continuous expansion period. When switched to a culture condition for terminal maturation, these immortalized erythroblasts gradually exit cell cycle, decrease cell size, accumulate hemoglobin, condense nuclei and eventually give rise to enucleated hemoglobin-containing erythrocytes. Our result may ultimately lead to the development of unlimited sources of cultured RBCs for optimally-matched or personalized transfusion medicine. We compared the global gene expression profiles of different human cell types: iE: immortalized erythroblasts generated by genetic reprogramming from pCBE; pCBE: primary cord blood-derived erythroblasts; CD34+: CD34+ purified hematopoietic stem/progenitor cells from adult blood or fetal liver; TF-1: a human erythroleukemia cell line; ESC: human embryonic stem cells; iPSCs: human induced pluripotent stem cells. We want to see the relationship among these cell types. We included multiple samples (biological replicates) for most cell types.
Project description:To facilitate comparative genomic analyses of human fetal and adult cells undergoing erythropoiesis, we employed a serum-free two-phase liquid culture system to expand and differentiate primary human CD34+ hematopoietic stem/progenitor cells (HSPCs) ex vivo. In this experimental context, highly enriched populations of stage-matched, differentiating, primary proerythroblasts (ProEs) were generated. We selected four time points (day 0, CD34+ HSPCs; day 3, 5, and 7, differentiating ProEs) that represented similar stages differentiation for gene expression profiling using microarrays. Primary maturing fetal or adult erythroblasts were generated ex vivo from CD34+ hematopoietic stem/progenitor cells (HSPCs) using a serum-free two-phase liquid culture system. Total RNA from primary fetal and adult HSPCs (day 0) and differentiating proerythroblasts (ProEs; day 3, 5, and 7) were extracted and used to hybridize to Affymetrix expression arrays using the HG-U133 Plus 2.0 platform.
Project description:CD34+ Haematopoietic stem cells were differentiated ex vivo to generate ChIP-seq data for machine learning of rules underlying open chromatin dynamics.
Project description:RNA-seq analysis was performed to compare differentially expressed genes in freshly isolated and ex-vivo cultured human cord blood CD34+ cells. Mitochondrion related genes are upregulated in CD34+ hematopoietic stem and progenitor cells upon ex vivo culture. In vivo transplantation experiments demonstrate that stemness of CD34+ cells is significantly decreased due to oxidative stress induced by ex vivo culture.
Project description:The supply of red blood cells (RBCs) is not sufficient in many developing countries or in developed countries for patients who need chronic transfusion from best-matched donors. Ex vivo expansion and maturation of human erythroid precursor cells (erythroblasts) could represent a potential solution. Proliferating erythroblasts can be expanded from human umbilical cord blood mononuclear cells (CB MNCs) ex vivo for 10^6-10^7 fold (in ~50 days) before undergoing senescence. Here, we report that ectopic expression of three to four genetic factors that have been used for iPS cell derivation enables CB-derived erythroblasts to undergo extended ex vivo expansion (≥10^51 fold in ~9 months) in a defined suspension culture condition without change of cell identity or function. These vastly expanding erythroblasts maintain homogeneously immature erythroblast phenotypes, a normal diploid karyotype and dependence on specific combination of cytokines and hormone for survival and proliferation throughout the continuous expansion period. When switched to a culture condition for terminal maturation, these immortalized erythroblasts gradually exit cell cycle, decrease cell size, accumulate hemoglobin, condense nuclei and eventually give rise to enucleated hemoglobin-containing erythrocytes. Our result may ultimately lead to the development of unlimited sources of cultured RBCs for optimally-matched or personalized transfusion medicine.
Project description:CD34+ Haematopoietic stem cells were differentiated under two ex vivo protocols to generate ATAC-seq data for machine learning of rules underlying open chromatin dynamics.
Project description:One of the long-standing goals in the field has been to establish a culture system that would allow maintenance of HSC properties ex vivo. In the absence of such system, the ability to model human hematopoiesis in vitro has been limited, and there has been little progress in the expansion of human HSCs for clinical application. To that end, we defined a mesenchyml stem cell co-culture system for expansion of clonally multipotent human HSPCs that are protected from apoptosis and immediate differentiation, and retain the HSPC phenotype. By performing a genome-wide gene expression analysis of purified HSPCs isolated at different stages of co-culture, we asked at the molecular level, to what degree hematopetic stem cell properties can be preserved during culture. This temporal gene expression data from in vivo derived- and ex vivo expanded human HSPCs will serve as a resource to identify novel regulatory pathways that control HSC properties, and to develop clinically applicable protocols for HSC expansion. Human CD34+ fetal liver cells were co-cultured on a subclone of OP9 stomal cells (OP9M2 sublemented with supportive cytokines (see below)). To distinguish between molecular changes acquired over prolonged culture versus immediately after exposure to culture, gene expression in isolated CD45+CD34+CD38-CD90+ HSPCs was assessed after 12 hours, 2 weeks and 5 weeks in culture. Cultured CD45+CD34+CD38-CD90+HSPCs were compared to freshly isolated CD45+CD34+CD38-CD90+HSPCs and their more differentiated CD45+CD34+CD38+CD90- downstream progenitor cells.
Project description:We used microarray profiling in erythroid cells to uncover TAL1 dependent genes in a hematopoietic differentiation context. Differentiated ex vivo hematopoietic multipotential progenitors isolated from adult peripheral blood. The knockdown of TAL1 (KD) was induced in pro-erythroblasts (Days 8 and 9 of differentiation) using lentivirus-delivered shRNA. A scramble (scr) shRNA sequence was used as a negative control.