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Pre-clinical Evaluation of Tyrosine Kinase Inhibitors for Treatment of Acute Leukemia
10:49

Pre-clinical Evaluation of Tyrosine Kinase Inhibitors for Treatment of Acute Leukemia

Published on: September 18, 2013

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Hematopoietic stem cell response to acute thrombocytopenia requires signaling through distinct receptor tyrosine

Beáta Ramasz1, Anja Krüger1, Julia Reinhardt2

  • 1Institute for Clinical Chemistry and Laboratory Medicine.

Blood
|August 23, 2019
PubMed

Although bone marrow niche cells are essential for hematopoietic stem cell (HSC) maintenance, their interaction in response to stress is not well defined. Here, we used a mouse model of acute thrombocytopenia to investigate the cross talk between HSCs and niche cells during restoration of the thrombocyte pool. This process required membrane-localized stem cell factor (m-SCF) in megakaryocytes, which was regulated, in turn, by vascular endothelial growth factor A (VEGF-A) and platelet-derived growth factor-BB (PDGF-BB). HSCs and multipotent progenitors type 2 (MPP2), but not MPP3/4, were subsequently activated by a dual-receptor tyrosine kinase (RTK)-dependent signaling event, m-SCF/c-Kit and VEGF-A/vascular endothelial growth factor receptor 2 (VEGFR-2), contributing to their selective and early proliferation. Our findings describe a dynamic network of signals in response to the acute loss of a single blood cell type and reveal the important role of 3 RTKs and their ligands in orchestrating the selective activation of hematopoietic stem and progenitor cells (HSPCs) in thrombocytopenia.

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