TAKIATA Hiroko HOKKAODO UNIV, DENT, ASSOCIATE, 歯学部, 教務職員 (30125330)
FUJISAWA Ryuichi HOKKAIDO UNIV, DENT, INSTRUCTOR, 歯学部, 助手 (40190029)
MIZUNO Morinichi HOKKAIDO UNIV, DENT, INSTRUCTOR, 歯学部, 助手 (10125354)
|Budget Amount *help
¥6,700,000 (Direct Cost : ¥6,700,000)
Fiscal Year 1991 : ¥600,000 (Direct Cost : ¥600,000)
Fiscal Year 1990 : ¥6,100,000 (Direct Cost : ¥6,100,000)
Although cell culture technology has greatly influenced the advance of modern biological sciences, it still remains in observations of two demensional phenomena using traditional flat cell-supporter of plastic dish. Since in any higher organism, most of the cells are surrounded by the three demensional extracellular matrix, we decided to develop three dimentional cell-supporter by using collagen, hydroxyapatite and related materials. We deviced and examined in vivo and in vitro at least seven different cell supporters including porous particles of hydroxyapatite (PPHAP), collagen beads, fibrous collagen membrane (FCM), and fibrous glass membrane (FGM).
In vivo experiments were done combining these new cell-supporters with bone morphogenetic protein (BMP) which had been purified by three steps of cromatographic procedure (S-300 fraction), and implanted into subcutaneous tissue of rats. Bone and cartilage formation were assayed by soft X-ray photography, histological observation, alkaline phosphatase activity, type II collagen, osteocalcin, DNA and calcium contents.
It was demonstrated that when porous partifcls of hydroxyapatite were implanted with purified BMP (S-300 fraction), bone was directly induccid without noticeable cartilage formation. On the other hand, fibrous glass membrane combined with BMP induced exclusively cartilage within the membrane accompanying a small amount of bone formation on the surface of the membrane.
These findings indicate that a typical growth factor, BMP is able to induce immature cells into becoming not only chondrogenic cells but also into becoming osteogenetic cells that form bone-like structures, depending upon the nature of the cell-supporter used for the implantation of this protein. The findings also suggest the importance of basic physics-chemical factors in matrix for cell differentiation.