Cells from three different human neuroblastoma cell lines and normal human bone marrow cells were exposed to the lipophilic fluorescent dye, merocyanine 540 (MC 540), and white light. In vitro clonogenic tumor cells were inactivated up to 25,000 times more rapidly than multipotent hematopoietic progenitor cells (CFU-GEMM). It is conceivable that this pronounced difference in sensitivity to MC 5...

Disrupted IKAROS activity is a recurrent feature of some human leukemias, but effects on normal human hematopoietic cells are largely unknown. Here, we used lentivirally mediated expression of a dominant-negative isoform of IKAROS (IK6) to block normal IKAROS activity in primitive human cord blood cells and their progeny. This produced a marked (10-fold) increase in serially transplantable mult...

Hematopoietic stem cells (HSCs) are self-renewing multipotent stem cells that generate mature blood lineages throughout life. They, together with hematopoietic progenitor cells (collectively known as HSPCs), emerge from hemogenic endothelium in the floor of the embryonic dorsal aorta by an endothelial-to-hematopoietic transition (EHT). Here we demonstrate that transforming growth factor β (TGFβ...

The hematopoietic cells are multipotent primitive cells, which differentiate into either common myeloid and lymphoid progenitor. However, if there an abnormality in this process of differentiation, condition leukemia arises, is the 11th leading cause cancer-related mortality worldwide year 2018. These abnormalities brought about by array mutations occurring at cellular level. According to two-h...

Infections and inflammation trigger neutrophilias that are supported by a hematopoietic program of accelerated granulopoiesis known as emergency granulopoiesis. The intrinsic factors that drive reactive neutrophilias and emergency granulopoiesis have been inferred but not demonstrated. Here, we show that alum cannot elicit reactive neutrophilias in IL-1R type I (IL-1RI)(-/-) mice, whereas other...

This review summarizes information regarding the rare population of very small embryonic-like stem cells (VSELs) that has been identified in adult tissues, emphasizing both their unique morphological features and potential biological significance. We focus on their pluripotent nature and expression of markers characteristic for embryonic stem cells (ESCs), epiblast (EP)SCs, and primordial germ ...

Growth factor independent 1 (Gfi1) is a transcriptional repressor originally identified as a gene activated in T-cell leukemias induced by Moloney-murine-leukemia virus infection. Notch1 is a transmembrane receptor that is frequently mutated in human T-cell acute lymphoblastic leukemia (T-ALL). Gfi1 is an important factor in the initiation and maintenance of lymphoid leukemias and its deficienc...

Lymphoid-primed multipotent progenitors with down-regulated megakaryocyte-erythroid (MkE) potential are restricted to cells with high levels of cell-surface FLT3 expression, whereas HSCs and MkE progenitors lack detectable cell-surface FLT3. These findings are compatible with FLT3 cell-surface expression not being detectable in the fully multipotent stem/progenitor cell compartment in mice. If ...

The erythroid stress cytokine erythropoietin (Epo) supports the development of committed erythroid progenitors, but its ability to act on upstream, multipotent cells remains to be established. We observe that high systemic levels of Epo reprogram the transcriptomes of multi- and bipotent hematopoietic stem/progenitor cells in vivo. This induces erythroid lineage bias at all lineage bifurcations...