Project description:Haematopoietic stem and progenitor cells (HSPCs) in the foetus and adult possess distinct molecular landscapes that regulate cell fate and change their susceptibility to initiation and progression of haematopoietic malignancies. The proteomic programs that govern these differences remain elusive. In this study, we have utilized a mass spectrometry-based quantitative proteomics approach to comprehensively describe and compare the proteome of foetal and adult HSPCs. We found that the proteome of foetal HSPCs is relatively simple, characterized by proteins involved in cell cycle and cell proliferation, while their adult counterparts are defined by a larger set of proteins that are involved in more diverse cellular processes. These adult characteristics include an arsenal of proteins important for viral and bacterial defence, as well as protection against ROS-induced protein oxidation. Our further analyses of Type I interferon signalling shows that foetal HSPCs are sensitive to Interferon a (IFNa), which impairs their production of mature lymphoid cells, whereas stimulation with IFNa to the pregnant mother enhances the production of early progenitors from foetal HSCs. Our results provide new and important insights into the molecular landscape of foetal and adult haematopoiesis that advance our understanding of normal and malignant haematopoiesis during foetal and adult life.
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:We characterized the genome wide occupancy of Med12 and p300 in mouse HSPCs. We also characterize p300 occupancy upon shRNA against control or Med12. ChIP-seq analysis of Med12 and/or p300 in untreated HSPCs
Project description:HLA-DR-lacking HSPCs [HLA-DR(-) HSPCs] were detected in aplastic anemia (AA) patients with HLA-DR15. HLA-DR(-) HSPCs may evade the attack by CD4+ T-cells recognizing the autoantigen presented by HLA-DR15. The goal of this study is to clarify the immune escape mechanisms from antigen-specific T-cells by comparing the trranscriptome profile of HLA-DR(+) HSPCs and HLA-DR(-) HSPCs.
Project description:Using iChIP, we map H3K27Ac, H3K4me3 and H3K4me1 in small populations (HSPCs) in the presence or absence of Med12 and identify affected super-enhancers. iChIP was performed using previously published protocols (Lara-Astiaso et al, 2014 Immunogenetics. Chromatin state dynamics during blood formation - Science, 345, 6199) Examination of histone modification in mouse HSPCs with and without Med12
Project description:Our results revealed that among all 273 metabolites detected, the levels of metabolites involved in glucose-related glycolysis and gluconeogenesis were elevated in GCN2 deleted HSPCs. Moreover, GCN2 deletion specifically increased mitochondrial OXPHOS and suppressed anaerobic glycolysis in HSPCs.