|Budget Amount *help
¥3,000,000 (Direct Cost: ¥3,000,000)
Fiscal Year 1990: ¥400,000 (Direct Cost: ¥400,000)
Fiscal Year 1989: ¥2,600,000 (Direct Cost: ¥2,600,000)
[Bone Morphogenetic Protein (BMP)]
Amino acid sequences of six bone morphogenetic proteins (BMPs) were reported by Wozney, j. et al. The amino acid sequences for our final highly purified protein from bovine bone show considerable homology to BMP-3.
[Bone substitute added with BMP]
In TCP (Tricalcium phosphate) or HA (Hydroxyapatite) mixed with BMP implanted into the mouse femoral muscle, it was confirmed that BMP induced bone formation around and on the surface of those particles. There were no difference between the yield of new bone of BMP/HA (Hydroxyapatite) or BMP/TCP (Tricalcium phosphate) composite. However, We found the yield of new bone of it was less than that of BMP alone. This would appeared to indicate that BMP was spread within a short period in vivo, and tissue differentiation was disturbed by HA or TCP. Therefore, an effective BMP delivery system from synthetic vehicle for concentrating BMP was required. Then we investigated the morphologic sequence of a response to a BMP/
PLP (Plaster of Paris) composite implanted into the mouse femoral muscle. Minimum crude BMP alone dose for bone induction was needed 3mg, on the other hand, in BMP/PLP (1 : 5) composite, that was reduced up to one mg. In more purified BMP (the activity was four times greater than that of crude-BMP), BMP dose was, furthermore, decreased up to 0.25mg in BMP/PLP (1 : 10) composite. Also the BMP/PLP composite implanted into the bone area of rat and monkey induced active bone formation. These results suggest that PLP composite system is one of the suitable BMP delivery systems currently available.
For the observation of clinical usefulness of BMP, autodecalcified dentin, it was already reported that BMP was included in the dentin, was prepared. That powder was implanted into bone defects after resection of oral and maxillofacial diseases. In results, autodecalcified dentin did not cause a foreign body reaction and inflammation, but we did not, contrary to expectation, confirmed bone formation induced by that dentin in roentgenograms. The some cause of it is to be sought that in partly clinical detection methods of induced bone by BMP, almost the deficiency of BMP in autodecalcified dentin and target cell in host tissue. These important problems must be solved in future. Less