Osteoblast characteristics of cells derived from human alveolar bone

Abstract

Bone is a dynamic tissue that is constantly remodeled throughout life. Remodeling implies the continuous of bone resorption followed by bone formation, which requires osteoblasts and osteoclasts. Bacterial infections are known to involve in bone pathology, by bacterial factors such as endotoxin and lipopolysaccharide (LPS). Many studies in vitro, demonstrated that LPS failed to directly stimulate the osteoclasts, but could indirectly stimulate via osteoblasts. Many studies attempt to isolate osteoblasts from bone fragments. The long bone and calvariae from fetal/neonatal rats and mice were popularly used in the primary cell culture systems. Despite the murine osteoblasts may demonstrate the different osteoblastic patterns from the human osteoblasts, only few studies used the human primary osteoblasts. The purpose of this study is to isolate and culture the cells from human alveolar bone and characterize their osteoblastic phenotypes. Alveolar bone were obtained from three 21 year-old healthy donors. After cultured in medium containing ascorbic acid and β-glycerophosphate at days 3, 7, 14, 21 and 28, we evaluated the expression of bone marker genes, collagen type I, alkaline phosphatase, bone sialoprotein, osteopontin and osteocalcin. In addition, we investigated the alkaline phosphatase activity and mineralized nodule formation. In this study, All samples expressed bone marker genes, and had alkaline phosphatase activity. They also formed the mineralized nodules. In conclusion, cells derived from human alveolar bone demonstrated osteoblast characterstics. These primary cells showed potential as an in vitro model of human osteoblasts from alveolar bone, for further studies of alveolar bone biology.