The effect of recombinant human bone morphogenetic protein-2 on the osteogenic potential of rat mesenchymal stem cells after several passages.
BACKGROUND
Since the osteogenic potential of bone marrow derived mesenchymal stem cells (BMSCs) becomes reduced with passage, establishment of culture condition that permit the rapid expansion of BMSCs while retaining their potential for differentiation is needed for clinical application. Bone morphogenetic proteins stimulate osteogenic differentiation in mesenchymal progenitor cells as well as increase stem cell numbers. Thus, we analyzed the effect of recombinant human bone morphogenetic protein-2 (rhBMP-2) on the osteogenic potential of rat BMSCs over several passages.


METHODS
Osteogenic differentiation in vitro was evaluated in terms of the alkaline phosphatase (ALP) activity and the osteocalcin (OC) concentration in the supernatants, and the expression of ALP and OC mRNA in the cultured cells. For in-vivo osteogenesis, BMSCs cultured with and without rhBMP-2 through all passages were implanted into athymic mice.


RESULTS
The levels of osteogenic markers were significantly higher in the cells of the BMP(+) group than in the cells of the BMP(-) group, although they decreased with passage irrespective of whether or not rhBMP-2 was added. Similar to the in-vitro experiments, there was a greater degree of bone and cartilage tissue formation in the BMP(+) group over all passages.


CONCLUSIONS
From our results, osteogenic potential can be maintained even in BMSCs that have been passaged several times in the presence of rhBMP-2. These cells are capable of inducing and participating in bone formation and can be used for clinical applications.
Ishikawa
Hisato
H
Department of Orthopaedic Surgery, Nagoya University School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, Aichi, 466-8550, Japan. h-ishi@med.nagoya-u.ac.jp
Kitoh
Hiroshi
H
Sugiura
Fumiaki
F
Ishiguro
Naoki
N
D000469:Alkaline Phosphatase / Q000378:metabolism; D000818:Animals; D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins / Q000494:pharmacology*; D002454:Cell Differentiation / Q000187:drug effects; D002478:Cells, Cultured; D006801:Humans; D059630:Mesenchymal Stem Cells / Q000187:drug effects* / Q000378:metabolism; D051379:Mice; D010006:Osteoblasts / Q000378:metabolism; D015675:Osteocalcin / Q000378:metabolism; D010012:Osteogenesis / Q000187:drug effects*; D016133:Polymerase Chain Reaction; D051381:Rats; D017207:Rats, Sprague-Dawley; D016212:Transforming Growth Factor beta / Q000494:pharmacology*
C525718:BMP2 protein, human; C525719:Bmp2 protein, mouse; C525720:Bmp2 protein, rat; D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins; D016212:Transforming Growth Factor beta; D015675:Osteocalcin; D000469:Alkaline Phosphatase