Otsuru Satoru, Tamai Katsuto, Yamazaki Takehiko, Yoshikawa Hideki, Kaneda Yasufumi
Division of Gene Therapy Science, Osaka University Graduate School of Medicine, 2-2 Yamada-oka, Suita, Osaka 565-0871, Japan.
Biochem Biophys Res Commun. 2007 Mar 9;354(2):453-8. doi: 10.1016/j.bbrc.2006.12.226. Epub 2007 Jan 10.
Recent studies have suggested the existence of osteoblastic cells in the circulation, but the origin and role of these cells in vivo are not clear. Here, we examined how these cells contribute to osteogenesis in a bone morphogenetic protein (BMP)-induced model of ectopic bone formation. Following lethal dose-irradiation and subsequent green fluorescent protein-transgenic bone marrow cell-transplantation (GFP-BMT) in mice, a BMP-2-containing collagen pellet was implanted into muscle. Three weeks later, a significant number of GFP-positive osteoblastic cells were present in the newly generated ectopic bone. Moreover, peripheral blood mononuclear cells (PBMNCs) from the BMP-2-implanted mouse were then shown to include osteoblast progenitor cells (OPCs) in culture. Passive transfer of the PBMNCs isolated from the BMP-2-implanted GFP-mouse to the BMP-2-implanted nude mouse led to GFP-positive osteoblast accumulation in the ectopic bone. These data provide new insight into the mechanism of ectopic bone formation involving bone marrow-derived OPCs in circulating blood.
最近的研究表明循环系统中存在成骨细胞，但这些细胞在体内的起源和作用尚不清楚。在此，我们研究了在骨形态发生蛋白（BMP）诱导的异位骨形成模型中这些细胞如何促进骨生成。对小鼠进行致死剂量照射并随后进行绿色荧光蛋白转基因骨髓细胞移植（GFP-BMT）后，将含BMP-2的胶原微球植入肌肉。三周后，新生成的异位骨中出现了大量GFP阳性成骨细胞。此外，来自植入BMP-2小鼠的外周血单个核细胞（PBMNC）在培养中显示含有成骨细胞祖细胞（OPC）。将从植入BMP-2的GFP小鼠分离的PBMNC被动转移到植入BMP-2的裸鼠中，导致异位骨中出现GFP阳性成骨细胞积累。这些数据为涉及循环血液中骨髓来源的OPC的异位骨形成机制提供了新的见解。
