The in vitro osteogenetic characteristics of primary osteoblastic cells from a rabbit calvarium

Abstract

Previously, we showed that recombinant human bone morphogenetic protein-2 (rhBMP-2) increased bone augmentation beyond the skeletal envelope within a titanium cap in a rabbit calvarium; many cuboidal osteoblastic cells were observed histologically. These results suggested that the new osteoblastic cells might have differentiated and matured via stimulation by rhBMP-2. To date, however, no studies have reported the characteristics of osteoblastic cells derived from adult rabbit calvarium, after addition of rhBMP-2. To determine the effects of rhBMP-2 on osteoblastic cells, we observed morphological characteristics and alkaline phosphatase activity of osteoblastic cells from an adult rabbit calvarium. The expression of proteins in the BMP signaling pathway and extracellular matrix were analyzed, and mineralized nodule formation was assessed. The alkaline phosphatase activity increased significantly after rhBMP-2 stimulation. The protein levels of phosphorylated-Smad1, Runx2, osteocalcin, osteopontin, and type I collagen were augmented by rhBMP-2 stimulation using Western blotting or ELISA; rhBMP-2 also stimulated mineralized nodule formation with alizarin red staining. The results suggest that primary osteoblastic cells derived from a rabbit calvarium have osteogenetic characteristics in vitro, underscoring the potential use of these cells as a model for studying bone formation. These cells may play an important role in in vivo bone augmentation in a rabbit experimental model. (J. Oral Sci. 50, [427][428][429][430][431][432][433][434] 2008)

Effect of diabetic osteoblasts on osteogenic differentiation of human umbilical cord mesenchymal stem cells

“…In the present study, the isolated cells from nondiabetics and diabetics had the characteristics of osteoblasts, and were identical to those seen in primary osteoblasts cultures 18 . After 1-3 weeks, the isolated cells became positive for type I collagen expression, alkaline phosphatase and deposited mineralized matrix as shown with the Alizarin staining.…”

Comparison of Osteogenic Differentiation of Embryonic Stem Cells and Primary Osteoblasts Revealed by Responses to IL-1β, TNF-α, and IFN-γ

“…In vitro osteogenic differentiation of primary osteoblasts [8][9][10][11][12][13]44] and ESCs [17][18][19][20][21] have both been well described, but there have been few comparative studies. In this study, both cell types showed expression of markers indicative of osteogenic differentiation and formed nodules comprising Values corrected to proportion of osteogenic control.…”

“…In vitro differentiation of osteoblasts results in the formation of distinct colonies of mineralized bone-like matrix, known as bone nodules [8,9]. The ECM deposited by osteoblasts in vitro has been shown to include collagen-I (col-I), fibronectin, osteocalcin (OCN), and osteopontin (OPN), and staining for these proteins is often most predominant around the mineralized nodules [10][11][12][13].…”

Characterization of Reversibly Immortalized Calvarial Mesenchymal Progenitor Cells

“…Restricted approval exists currently for select indications in the craniofacial skeleton (e.g., BMP-2 in alveolar clefts). Although not yet fully approved for the entire craniofacial skeleton, in vitro and in vivo studies have been promising regarding the use of BMPs and their induction of osteogenesis of explanted calvarial cells and defect closure [7, 8]. Smith et al demonstrated that the treatment of large scale calvarial defects in rabbits with rhBMP-2 induced complete resolution of defects within six weeks [8].…”