Osteoblasts, which are derived from pluripotent mesenchymal stem cells (MSCs), play an important role in hematopoiesis. Human parathyroid hormone (hPTH) induces osteoblasts to produce many factors that are essential to hematopoietic stem cells. However, little is known about the impact of hPTH on MSCs to enhance hematopoiesis. We determined the optimal dose of hPTH that was necessary in vitro for increased osteoblast function. In addition, we compared MSC and osteoblast function to explore the role of hPTH in hematopoiesis. The mRNA expression levels of granulocyte colony-stimulating factor (G-CSF), granulocyte macrophage colony-stimulating factor (GM-CSF), interleukin 6, stromal cell-derived factor 1, insulin-like growth factor 1 (IGF-1), IGF-2, insulin-like growth factor–binding protein 1 (IGFBP-1), IGFBP-2, and IGFBP-3 were comparable in osteoblasts and human cord blood-derived MSCs. However, G-CSF, GM-CSF, IGF-2, IGFBP-1, IGFBP-2, and IGFBP-3 expression levels in osteoblasts were markedly increased after treatment with 50 or 100 nM of hPTH. In conclusion, hPTH does not affect the ability of MSCs to differentiate into osteoblasts. In addition, hPTH may enhance hematopoiesis by activating the IGF system (IGF-2, IGFBP-1, IGFBP-2, and IGFBP-3) and hematopoietic growth factors (G-CSF and GM-CSF) in osteoblasts, but not in MSCs.
*Department of Pediatrics, Wonkwang University Sanbon Medical Center, Gunpo, Korea
†Graduate School of Biomedical Science & Engineering, Hanyang University
§Department of Pediatrics, Hanyang University Medical Center
∥Biomedical Research Institute, MEDIPOST Co. Ltd., Seoul, Korea
¶Department of Genetics, Hanyang University College of Medicine
‡Department of Pediatrics, Chungnam University Hospital, Daejeon, Korea
J.-H.L. and K.-J.H. contributed equally.
Supported by a grant of the Korea Healthcare technology R&D Project (A101712), Ministry for Health & Welfare, Republic of Korea and by a grant from the Korea Science and Engineering Foundation (2010-0029508) through the MRC for Regulation of Stem Cell Behaviors at Hanyang University College of Medicine, Republic of Korea.
The authors declare no conflict of interest.
Reprints: Young-Ho Lee, MD, PhD, 222 Wangsimni-ro, SeongDong-gu, Seoul 133-792, Korea (e-mail: firstname.lastname@example.org).
Received October 8, 2011
Accepted June 26, 2012