Much controversy surrounds the identity and origin of human hepatic stem and progenitor cells in part because of a lack of small animal models in which the developmental potential of isolated candidate cell populations can be functionally evaluated. We show here that adoptive transfer of CD34(+) cells from human fetal liver into sublethally irradiated NOD-SCID Il2rg(-/-) (NSG) mice leads to an ...

introduction  insulin-like growth factor i (igf-i) which is produced in abundance in the normal adult liver, is deeply involved in hepatocyte survival, growth, and differentiation during liver development. igf-i plays the roles via the receptor (igf-ir) signaling pathway. igf-ir unlike igf-i is expressed strongly in the developing liver, but much more weakly in adults. objective:  we hypothesiz...

Cytokine-supported ex vivo expansion of peripheral blood progenitor cells (PBPCs) offers new perspectives for autografting after high-dose chemotherapy. One of the potential advantages is the possibility to reduce the volume of blood processed from the patient, thus allowing reduction of the overall tumor cell number in the final autograft. However, ex vivo expansion will only be advantageous i...

Identification and enumeration of human hematopoietic stem cells remain problematic, since in vitro and in vivo stem cell assays have different outcomes. We determined if the altered expression of adhesion molecules during stem cell expansion could be a reason for the discrepancy. CD34+CD38- and CD34+CD38+ cells from umbilical cord blood were analyzed before and after culture with thrombopoieti...

Adipose-derived stem cells (ADSCs) have the potential to differentiate into various cell lineages and they are easily obtainable from patients, which makes them a promising candidate for cell therapy. However, a drawback is their limited life span during in vitro culture. Therefore, hTERT-immortalized CD34+ and CD34- mouse ADSC lines (mADSCshTERT) tagged with GFP were established. We evaluated ...

Marked sequence variation in the mtDNA control region has been observed in human single CD34(+) cells, which persist in vivo and are present also in differentiated hematopoietic cells. In this study, we analyzed 5071 single CD34(+) cells from 49 individuals (including 31 maternally related members from four families and 18 unrelated donors) in order to determine the mutation spectrum within the...

INTRODUCTION Treatment failure in acute myeloid leukemia is probably caused by the presence of leukemia initiating cells, also referred to as leukemic stem cells, at diagnosis and their persistence after therapy. Specific identification of leukemia stem cells and their discrimination from normal hematopoietic stem cells would greatly contribute to risk stratification and could predict possible ...

We hypothesized that endothelial progenitor cells derived from individuals with diabetes would exhibit functional defects including inability to respond to hypoxia and altered paracrine/autocrine function that would impair the angiogenic potential of these cells. Circulating mononuclear cells isolated from diabetic (n = 69) and nondiabetic (n = 46) individuals were used to grow endothelial colo...

Low levels of telomerase activity have recently been detected in human primitive hematopoietic cells, however, blood cells exhibit telomere shortening on cell proliferation. This challenging observation led us to study telomerase regulation and telomere length in human hematopoietic progenitor cells from fetal liver (FL), cord blood (CB), peripheral blood (PB), and bone marrow (BM). We found te...