Background aims. For engineering bone tissue to restore, for example, maxillofacial defects, mechanosensitive cells are needed
that are able to conduct bone cell-specific functions, such as bone remodelling. Mechanical loading affects local bone mass
and architecture in vivo by initiating a cellular response via loading-induced flow of interstitial fluid. After surgical
removal of ectopically impacted third molars, human dental pulp tissue is an easily accessible and interesting source of cells
for mineralized tissue engineering. The aim of this study was to determine whether human dental pulp-derived cells (DPC) are
responsive to mechanical loading by pulsating fluid flow (PFF) upon stimulation of mineralization in vitro.
Human DPC were incubated with or without mineralization medium containing differentiation factors for 3 weeks. Cells were
subjected to 1-h PFF (0.7 0.3 Pa, 5 Hz) and the response was quantifi ed by measuring nitric oxide (NO) and prostaglandin
E 2 (PGE 2 ) production, and gene expression of cyclooxygenase (COX)-1 and COX-2.
Results. We found that DPC are intrinsically
mechanosensitive and, like osteogenic cells, respond to PFF-induced fluid shear stress. PFF stimulated NO and PGE 2 production,
and up-regulated COX-2 but not COX-1 gene expression. In DPC cultured under mineralizing conditions, the PFF-induced NO, but
not PGE 2 , production was signifi cantly enhanced.
Conclusions. These data suggest that human DPC, like osteogenic cells,
acquire responsiveness to pulsating fluid shear stress in mineralizing conditions. Thus DPC might be able to perform bone-like
functions during mineralized tissue remodeling in vivo , and therefore provide a promising new tool for mineralized tissue
engineering to restore, for example, maxillofacial defects.