Project description:Rapid expansion of stress erythroid progenitors is a key response to acute anemia during stress erythropoiesis. Besides the rapidly amplifying progenitors, a small population of stem-cell like erythroid progenitors undergoes limited number of cell divisions and maintains their stemness. In this study, we addressed the differences in expression profiles of regulatory genes between two stress erythroid progenitor populations that were identified by proliferation capacity and physiological status. We used microarrays to detail the gene expression profiles of stem-cell like stress erythroid progenitors and rapidly amplifying stress erythroid progenitors during stress erythropoiesis.
Project description:Inflammation inhibits steady state erythropoiesis, while at the same time it induces stress erythropoiesis to maintain erythroid homeostasis. Stress erythropoiesis relies on the rapid expansion of early progenitors that do not differentiate until the increase in serum Epo promotes a transition in progenitors to enable their synchronous differentiation. RNA-seq analysis allows us to identify an inflammatory transcriptome signature in early progenitors that induces iNOS-derived NO production. The accumulation of NO establishes a metabolism that promotes cell proliferation while inhibiting the differentiation of early progenitors. In contrast, the transition of progenitors to differentiation is marked by the suppressed inflammatory responses and a consequent decrease of iNOS-derived NO. We show that Epo initiates this transition response by altering progenitor metabolism to support itaconate production, resulting in the activation of Nrf2 that suppresses the inflammatory responses, which in turn alleviates the NO-mediated inhibition of erythroid program. Consequent differentiation of stress erythroid progenitors generates a bolus of new erythrocytes to maintain erythroid homeostasis until steady state erythropoiesis can resume.
Project description:CD34+ progentitors were isolated from the bone marrow of three healthy volunteers. CD34+CD71+CD45RA- were FACS sorted to enrich for erythroid progenitors. The cells were cultured for four hours with or without EPO in combination with LY294002, and harvested for RNA extraction, amplification and expression analysis.
Project description:CD34+ progenitors were isolated from the bone marrow of three healthy volunteers. CD34+CD71+CD45RA- were FACS sorted to enrich for erythroid progenitors. The cells were cultured for four hours with or without EPO in combination with LY294002, and harvested for RNA extraction, amplification and expression analysis. A compound treatment design type is where the response to administration of a compound or chemical (including biological compounds such as hormones) is assayed. Compound Based Treatment: EPO Keywords: compound_treatment_design
Project description:The study aims to show that Sox9+ Chd1+ mouse embryonic lung progenitors can be isolated and expanded long-term in 3D culture while maintaining their multipotency. in vitro cultured Sox9+ Chd1+ lung progenitors transcriptionally resemble their in vivo counterparts and show significant difference from adult lung epithelial (Cdh1+ and EpCAM+) and non-epithelial (Cdh1- and EpCAM-) cells
Project description:Hereditary Persistence of Fetal Hemoglobin (HPFH) is characterized by persistent high levels of fetal hemoglobin (HbF) in adults. Several contributory factors, both genetic and environmental, have been identified, but others remain elusive. Ten of twenty-seven members from a Maltese family presented with HPFH. A genome-wide SNP scan followed by linkage analysis revealed a candidate region on chromosome 19p13.12-13. Sequencing identified a nonsense mutation in the KLF1 gene, p.K288X, ablating the DNA binding domain of this key erythroid transcriptional regulator. Only HPFH family members were heterozygote carriers of this mutation. Expression profiling on primary erythroid progenitors revealed down-regulation of KLF1 target genes in HPFH samples. Functional assays demonstrated that, in addition to its established role in adult globin expression, KLF1 is a critical activator of the BCL11A gene, encoding a suppressor of HbF expression. These observations provide a rationale for the effects of KLF1 haploinsufficiency on HbF levels. To identify differentially expressed genes, RNA was isolated from erythroid progenitors (HEPs) cultured from peripheral blood of four HPFH (KLF1 p.K288X/wt) and four non-HPFH family members (wt/wt) and used for genome-wide expression analysis.
Project description:MYB plays a critical role as a regulator of erythropoieisis. We have shown that MYB silences epsilon and gamma-globin expression in erythroid progenitors. We here examine erythroid cells at the basophilic erythroblast stage of differentiation with MYB shRNA or control lentiviral transduction prior to differentiation. We have cultured CD34 cells and transduced the cells with lentiviruses harboring shRNAs targeting MYB or controls and then allowed the cells to differentiate down the erythroid lineage. At the basophilic erythroblast stage of differentiation, the cells were harvested and total RNA was extracted. This was used to hybridize to Affymetrix expression arrays using the HG-U133 Plus 2.0 platform to ascertain expression differences that occur with the knockdown of MYB.