The Hematopoietic Stem Cell in its Place

Harvard University, Cambridge, Massachusetts, United States
Nature Immunology (Impact Factor: 20). 05/2006; 7(4):333-7. DOI: 10.1038/ni1331
Source: PubMed


A signature characteristic of stem cells is their ability to self-renew, affording a theoretically limitless ability to produce daughter cells and their descendents. This near-timeless dimension of stem cell function is not free of the constraints of place. The idea that highly specialized 'microenvironmental' cues participate in the regulation of stem cells has evidence in classic embryology and more recently in adult stem cells through the use of model organisms. There is now ample evidence that an anatomically defined, specifically constituted place represents the niche for hematopoietic and other tissue-specific stem cells. This review provides a conceptual framework and detailed account of the hematopoietic stem cell niche as defined at present. The components are assembling into a more complex view of the niche and may now be amenable to examination as a system and possibly to alteration to affect outcomes in immune regeneration.

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Available from: Gregor B. Adams, Jun 08, 2015
    • "These precursors, originate mature cells through progressive cell differentiation and, in some of the phases, intensive proliferation [Huang et al., 2007]. Compared to mature lymphocytes, HPC have different signal requirements for survival or apoptosis induction and undergo complex processes [Adams and Scadden, 2006]. The development of B and T cells bearing antigen-specific receptors requires gene rearrangements with consequent generation of double strand breaks (and DNA repair) followed by intense cell proliferation, rendering lymphocytes susceptible to oncogenic transformation. "
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    • "Th e interaction between stem cells and their niche involves the interplay of many factors, including extracellular matrix (ECM) molecules, cell-cell contacts, and cytokines. Th is interplay critically balances cell cycling and quiescence, leading to proliferation or apoptosis, and selfrenewal or diff erentiation, respectively (Adams and Scadden 2006, Wilson and Trumpp 2006, Yin and Li 2006). Several stem cell niches have been described for diverse adult stem cells, which contribute to tissue homeostasis of an organism and are located inside the bone marrow, retina, cornea, gastrointestinal tract, pancreas, etc. "
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