Wnt modulators, SFRP-1, and SFRP-2 are expressed in osteoblasts and differentially regulate hematopoietic stem cells

Hideaki Nakajima, Miyuki Ito, Yoshihiro Morikawa, Tadasuke Komori, Yumi Fukuchi, Fumi Shibata, Shinichiro Okamoto, Toshio Kitamura

Research output: Contribution to journalArticle

19 Citations (Scopus)


Wnt signaling has been implicated in the self-renewal of hematopoietic stem cells (HSCs). Secreted frizzled-related proteins (SFRPs) are a family of soluble proteins containing a region homologous to a receptor for Wnt, Frizzled, and are thought to act as endogenous modulators for Wnt signaling. This study examined the role of SFRPs in HSC regulation. Among the four family members, SFRP-1 and SFRP-2 are specifically induced in the bone marrow in response to myelosuppression, and immunostaining revealed that both proteins were expressed in osteoblasts. Interestingly, SFRP-1 reduced the number of multipotent progenitors in in vitro culture of CD34-KSL cells, while SFRP-2 did not. Furthermore, SFRP-1 compromised the long-term repopulating activity of HSCs, whereas SFRP-2 did not affect or even enhanced it in the same setting. These results indicate that although both SFRP-1 and SFRP-2 act as inhibitors for Wnt signaling in vitro, they differentially affect the homeostasis of HSCs.

Original languageEnglish
Pages (from-to)65-70
Number of pages6
JournalBiochemical and Biophysical Research Communications
Issue number1
Publication statusPublished - 2009 Dec 4



  • Hematopoietic stem cells
  • Osteoblast
  • SFRP
  • Secreted frizzled-related protein
  • Self-renewal
  • Wnt

ASJC Scopus subject areas

  • Biophysics
  • Biochemistry
  • Molecular Biology
  • Cell Biology

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