| Literature DB >> 18371409 |
Hiroki Yoshihara1, Fumio Arai, Kentaro Hosokawa, Tetsuya Hagiwara, Keiyo Takubo, Yuka Nakamura, Yumiko Gomei, Hiroko Iwasaki, Sahoko Matsuoka, Kana Miyamoto, Hiroshi Miyazaki, Takao Takahashi, Toshio Suda.
Abstract
Maintenance of hematopoietic stem cells (HSCs) depends on interaction with their niche. Here we show that the long-term (LT)-HSCs expressing the thrombopoietin (THPO) receptor, MPL, are a quiescent population in adult bone marrow (BM) and are closely associated with THPO-producing osteoblastic cells. THPO/MPL signaling upregulated beta1-integrin and cyclin-dependent kinase inhibitors in HSCs. Furthermore, inhibition and stimulation of THPO/MPL pathway by treatments with anti-MPL neutralizing antibody, AMM2, and with THPO showed reciprocal regulation of quiescence of LT-HSC. AMM2 treatment reduced the number of quiescent LT-HSCs and allowed exogenous HSC engraftment without irradiation. By contrast, exogenous THPO transiently increased quiescent HSC population and subsequently induced HSC proliferation in vivo. Altogether, these observations suggest that THPO/MPL signaling plays a critical role of LT-HSC regulation in the osteoblastic niche.Entities:
Mesh：
Substances：
Year: 2007 PMID： 18371409 DOI： 10.1016/j.stem.2007.10.020
Source DB: PubMed Journal: Cell Stem Cell ISSN： 1875-9777 Impact factor: 24.633