Model for in vitro investigation of bone mineralization.

An in vitro model was developed for the investigation of bone cell mineralization processes. Out-grown cells of explanted human nasal bone fragments were selected into three lineages and one of them, the osteoblast-enriched line, was partially characterized. A large number of cells of this line stained readily for alkaline phosphatase. They produced prostanoids, PGl2, PGF2 alpha and PGE2, and osteocalcin in the presence of 1,25(OH)2D3. Cells synthesized collagen and mineralized the developed extracellular matrix. This latter line seems to be appropriate as a model system to find effective compounds which increase bone calcification.