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Research Containing: Hematopoietic Stem Cells/cytology/metabolism

Properties of mechano-transduction via simulated microgravity and its effects on intracellular trafficking of VEGFR's

by on 9 June 2015in Biology & Biotechnology No comment

This study emphasizes the dynamical properties of mechanical loading via simulated microgravity, its effect on acute myeloid leukemia proliferation and hematopoietic stem cell (HSPC) growth and its implications in the area of tissue regeneration. Data presented illustrates that mechanical transduction changes the expression of humoral factors by facilitating paracrine/autocrine signalling, therefore modulating intracellular trafficking of tyrosine kinase receptors. Understanding mechano-transduction in the context of cell and tissue morphogenesis is the major focus of this study. The effects of external physiological stresses, such as blood flow, on several cellular subtypes seem to produce very intricate cellular responses. It is well accepted that mechanical loading plays an intrinsic and extrinsic influence on cell survival. This study shows how microgravity effects hematopoietic stem cells, and human leukemic cell proliferation and expression of its receptors that control cell survival, such as the tyrosine kinase vascular endothelial growth factor receptor-1, receptor-2 and receptor-3.

Related URLs:
http://ovidsp.ovid.com/ovidweb.cgi?T=JS&CSC=Y&NEWS=N&PAGE=fulltext&D=emed10&AN=2012656922
http://sfxhosted.exlibrisgroup.com/mayo?sid=OVID:embase&id=pmid:&id=doi:&issn=1949-2553&isbn=&volume=3&issue=4&spage=426&pages=426-434&date=2012&title=Oncotarget&atitle=Properties+of+mechano-transduction+via+simulated+microgravity+and+its+effects+on+intracellular+trafficking+of+VEGFR%27s&aulast=Puca&pid=%3Cauthor%3EPuca+A.%3C%2Fauthor%3E&%3CAN%3E2012656922%3C%2FAN%3E

Floating culture promotes the maintenance of hematopoietic stem cells

by on 9 June 2015in Biology & Biotechnology No comment

In this study we examined the effect of the specific gravity of culture medium on the frequency of hematopoietic stem cell (HSC) maintenance. We used a newly developed high-specific-gravity media. Bone marrow cells were isolated and cultured, and HSC activity was evaluated. The number of hematopoietic progenitor/stem cells was markedly higher in the medium with high specific gravity. In high-specific-gravity media, cells did not precipitate, maintenance of HSCs was increased, and there was a concomitant accumulation of beta-catenin. This novel technique for maintaining HSC populations provides an important new tool for studies in regenerative medicine. (c) 2007 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

Related URLs:
<Go to ISI>://WOS:000250102900017

Unique Differentiation Profile of Mouse Embryonic Stem Cells in Rotary and Stirred Tank Bioreactors

by on 9 June 2015in Biology & Biotechnology No comment

Embryonic stem (ES)-cell-derived lineage-specific stem cells, for example, hematopoietic stem cells, could provide a potentially unlimited source for transplantable cells, especially for cell-based therapies. However, reproducible methods must be developed to maximize and scale-up ES cell differentiation to produce clinically relevant numbers of therapeutic cells. Bioreactor-based dynamic culture conditions are amenable to large-scale cell production, but few studies have evaluated how various bioreactor types and culture parameters influence ES cell differentiation, especially hematopoiesis. Our results indicate that cell seeding density and bioreactor speed significantly affect embryoid body formation and subsequent generation of hematopoietic stem and progenitor cells in both stirred tank (spinner flask) and rotary microgravity (Synthecon (TM)) type bioreactors. In general, high percentages of hematopoietic stem and progenitor cells were generated in both bioreactors, especially at high cell densities. In addition, Synthecon bioreactors produced more sca-1(+) progenitors and spinner flasks generated more c-Kit(+) progenitors, demonstrating their unique differentiation profiles. cDNA microarray analysis of genes involved in pluripotency, germ layer formation, and hematopoietic differentiation showed that on day 7 of differentiation, embryoid bodies from both bioreactors consisted of all three germ layers of embryonic development. However, unique gene expression profiles were observed in the two bioreactors; for example, expression of specific hematopoietic genes were significantly more upregulated in the Synthecon cultures than in spinner flasks. We conclude that bioreactor type and culture parameters can be used to control ES cell differentiation, enhance unique progenitor cell populations, and provide means for large-scale production of transplantable therapeutic cells.

Related URLs:
<Go to ISI>://WOS:000283899600001