Background: Alveolar bone destruction is a characteristic feature of period
ontal diseases and multinucleated osteoclast cells derived from hemopoietic
cells are responsible for bone resorption. Treponema lecithinolyticum is a
novel oral spirochete isolated from the periodontal lesions.
Methods: The effect of whole cell sonicates on the osteoclast differentiati
on was examined in a co-culture system of hemopoietic mouse bone marrow cel
ls and calvaria derived-osteoblastic cells to clarify the role of T. lecith
inolyticum in the alveolar bone destruction associated with periodontal dis
eases. The differentiated osteoclasts were confirmed by tartrate-resistant
acid phosphatase (TRAP) staining.
Results: Sonicates of this bacterium stimulated the osteoclast formation in
the co-culture system in a dose-dependent manner. The sonicates-induced os
teoclast formation was partially inhibited by the heat treatment of sonicat
es. Indomethacin, which is a prostaglandin inhibitor, decreased the osteocl
ast formation induced by the bacterial sonicates.
Conclusions: These findings suggest that T. lecithinolyticum induces osteoc
last differentiation by a prostaglandin E-2-dependent mechanism and that he
at-labile components may be involved in this process.