Lf. Cooper et al., SPATIOTEMPORAL ASSESSMENT OF FETAL BOVINE OSTEOBLAST CULTURE DIFFERENTIATION INDICATES A ROLE FOR BSP IN PROMOTING DIFFERENTIATION, Journal of bone and mineral research, 13(4), 1998, pp. 620-632
Fetal bovine mandible-derived osteoblasts were cultured for the purpos
e of obtaining a spatiotemporal assessment of bone matrix protein expr
ession during in vitro differentiation, The results obtained from elec
tron microscopic, immunohistological, biochemical, and molecular biolo
gical analyses indicated that these primary cultured osteoblasts produ
ce an abundant extracellular matrix which mineralizes during a 14-day
culture period, During this process, a restricted, spatiotemporal patt
ern of bone sialoprotein expression was indicated by immunohistologica
l and molecular evaluations, To test the possibility that bone sialopr
otein promoted the continued morphodifferentiation of osteoblastic cel
ls, cultures were grown in the presence of anti-bone sialoprotein anti
bodies known to interfere with cell-bone sialoprotein attachment, Comp
ared with cultures grown in the presence of normal rabbit serum (1:150
), cultures grown in the media containing anti-bone sialoprotein antib
ody (1:150) failed to mineralize as demonstrated by von Kossa staining
and failed to express osteocalcin and osteopontin as shown by the rev
erse transcription polymerase chain reaction, These results contribute
to the growing evidence that bone sialoprotein Is an important determ
inant of osteoblast differentiation and bane formation, Matrix protein
-cell interactions may be examined using this spatiotemporally defined
model.