|Title||The dualism of nacre|
|Publication Type||Journal Article|
|Year of Publication||2004|
|Authors||Lopez, E, Milet, C, Lamghari, M, Mouries, LP, Borzeix, S, Berland, S|
The nacreous part of the shell of Pinctada maxima, bivalve mollusk, was used in these studies. In vivo studies, carried out on adult sheep, showed that implanted pieces of nacre pass bone acceptance. Nacre implants were not subjected to intolerance reaction and the recipient bone provided with nacre underwent a sequence of bone regeneration within an osteoprogenitor rich cell layer. Newly formed bone and nacre welded into a dual biomineralized unit. For in vitro studies, the water soluble organic matrix was extracted from powdered nacre by a gentle non-decalcifying process. Three mammalian cell types, fibroblasts (human), bone marrow stromal cells (rat) and pre-osteoblasts (mouse) were used to characterize the effect of nacre water soluble matrix (WSM) on mammal cell recruitment and differentiation in the osteogenic pathway. Alkaline phosphatase activity and osteocalcine expression, markers of cell stimulation and osteoblastic differentiation, were analysed in the culture models. In vitro studies provided evidence for the presence, in nacre organic matrix, of signal molecules responsible for the recruitment of mammal cells in the osteogenic pathway and bone cell activation undergoing a complete sequence of mineralization.