BACKGROUND Adult hematopoietic stem cells (HSCs), the ideal system for regenerative research, were isolated at single cell levels decades ago, whereas studies on embryonic HSCs are much more difficult. METHODS Zhou et al identified a new pre-HSC cell surface marker, CD201, by which they isolated pre-HSCs at single cell levels for further analyses. RESULTS The novel expression pattern of HSC...

Apilot study by Wu et al. (1) suggests that umbilical cordYderived mesenchymal stem cells (UCMSCs) promote hematopoietic engraftment when cotransplanted with cord blood (CB) cells (Fig. 1A). The authors make good use of two somatic stem cells, both derived from umbilical cord. Together with the establishment of their UCMSC bank, their trial appears to be potentially meaningful for future develo...

Small numbers of hematopoietic stem cells (HSCs) generate large numbers of mature effector cells through the successive amplification of transiently proliferating progenitor cells. HSCs and their downstream progenitors have been extensively characterized based on their cell-surface phenotype and functional activities during transplantation assays. These cells dynamically lose and acquire specif...

Hematopoietic stem cells (HSCs) are maintained in a hypoxic niche to limit oxidative stress. Although iron elicits oxidative stress, the importance of iron homeostasis in HSCs has been unknown. Here we show that iron regulation by the F-box protein FBXL5 is required for HSC self-renewal. Conditional deletion of Fbxl5 in mouse HSCs results in cellular iron overload and a reduced cell number. Bon...

TIF1β is a transcriptional corepressor that recruits repressive chromatin modifiers to target genes. Its biological function and physiological targets in somatic stem cells remain largely unknown. Here, we show that TIF1β is essential for the maintenance of hematopoietic stem cells (HSCs). Deletion of Tif1b in mice induced active cycling and apoptosis of HSCs and promoted egression of HSCs from...

BACKGROUND & AIMS MicroRNAs (miRNAs) have been shown to play essential roles in HSCs activation which contributes to hepatic fibrosis. Our previous miRNA microarray results suggested that miR-126 might be decreased during HSCs activation as other studies. The aim of this study is to investigate the role of miR-126 during HSCs activation. METHODS In this study, the expression of miR-126 during...

Abstract A promising strategy to increase the numbers of hematopoietic stem cells (HSCs) for clinical applications, like cell transplantation, is offered by advanced in vitro culture systems. We developed artificial 3D bone marrow-like scaffolds made polydimethylsiloxane (PDMS) mimicking natural HSC niche . These PDMS combination with an optimized medium allow amplification high undifferentiate...

Umbilical cord blood (UCB) is an attractive source of hematopoietic stem and progenitor cells for hematopoietic stem cell (HSC) transplantation. However, the low number of HSCs obtainable from a single donor of UCB limits direct transplantation of UCB to the treatment of pediatric patients. In this study, we investigated the ex vivo expansion of HSCs cultured on biomaterials grafted with severa...

The concept of lymphoid differentiation in the human gastrointestinal tract is controversial but is the focus of this study, which examined adult human small intestinal tissue for the presence of CD34(+)CD45(+) hemopoietic stem cells (HSCs) and lymphoid progenitors. Flow cytometry demonstrated that over 5% of leukocytes (CD45(+) cells) isolated from human gut were HSCs coexpressing CD34, a sign...

Bone marrow hematopoietic stem cells (HSCs) are crucial to maintain lifelong production of all blood cells. Although HSCs divide infrequently, it is thought that the entire HSC pool turns over every few weeks, suggesting that HSCs regularly enter and exit cell cycle. Here, we combine flow cytometry with label-retaining assays (BrdU and histone H2B-GFP) to identify a population of dormant mouse ...