Grant-in-Aid for General Scientific Research (B)
|Allocation Type||Single-year Grants |
|Research Institution||The University of Tokushima |
MATSUMOTO Naoyuki The University of Tokushima, School of Dentistry, Professor, 歯学部, 教授 (00013871)
YAMASHITA Kikuji The University of Tokushima, School of Dentistry, Research Associate, 歯学部, 助手 (30182497)
OKAMOTO Yasuo The University of Tokushima, University Dental Hospital, Research Associate, 歯学部附属病院, 助手 (50213989)
HORIUCHI Masanobu The University of Tokushima, School of Dentistry, Research Associate, 歯学部, 助手 (10219214)
ICHIKAWA Tetsuo The University of Tokushima, University Dental Hospital, Assistant Professor, 歯学部附属病院, 講師 (90193432)
MIYAMOTO Masashi The University of Tokushima, School of Dentistry, Research Associate, 歯学部, 助手 (30145007)
|Project Period (FY)
1989 – 1991
Completed (Fiscal Year 1991)
|Budget Amount *help
¥6,500,000 (Direct Cost: ¥6,500,000)
Fiscal Year 1991: ¥700,000 (Direct Cost: ¥700,000)
Fiscal Year 1990: ¥1,600,000 (Direct Cost: ¥1,600,000)
Fiscal Year 1989: ¥4,200,000 (Direct Cost: ¥4,200,000)
|Keywords||osteoinductive factor / aterocollagen / hydroxyapatite / alkaline phosphatase / acellular mineral deposition / satellite cell / 生体材料 / 骨芽細胞 / 軟骨芽細胞 / 石灰化|
Decalcified bovine bone matrix powder was extracted dessociatively in 4 M guanidine hydrochloride and the water soluble proteins of the extract was collected (Fraction I). Then, the partial purified fraction (Fraction II) was obtained from fraction I by using heparin-sepharose chromatography and gel-exclusion chromatography. Fraction I or II adsorbed to aterocollagen were bioassayed by intramuscular implantation in rats. Fraction II had approximately 680 times activity as much as fraction I, as measured by alkaline phosphatase activity of the mineralized implant. Final fraction was purified by using reverse-phase HPLC. Electrophoresis of this fraction revealed a band with an apparent molecular mass of 18 kDa.
The following methods have been developed to decide osteoinduclive ability in just a few days.
1) in vitro
A hard tissue is formed in our co-culture system which contains the osteoinductive factor and mesenchymal cells derived from rat skeletal muscle tissue or rat calvaria subperiosteum, which have a high responsibility to that factor.
2) in vivo
Osteoinductive activity is demonstrated by some histological or/and biochemical parameters of bone tissue, which is induced by implantation of the complex of osteoinductive factor and aterocollagen.
Some new findings about the mechanism of osteoinduction has been revealed by the investigations on the implantation of partial purified osteoinductive factor.
1) Acellular mineral deposition, which appeared in bone matrix gelatin preceding bone induction may be significant for differentiation of osteoblast.
2) Muscle satellite cells will differentiate into osteoblasts.
3) Porous hydroxyapatite block and aterocollagen are valid as a carrier for osteoinductive factor.