Influence of La ³⁺on the Osteogenesis of Tissue Engineering Bone

Objective:To observe the influences of lanthanum chloride(La ³⁺) on the osteogenesis of tissue-engineering bone implanted into the autologous bony defects of dog jaws.

Materials and Methods:BMSCs from the adult dog (n=9) marrow were separated by density gradient centrifugation, cultured in vitro and induced to be osteoblast.The third generation BMSCs were interfered with La ³⁺ of 5.564ug/ml and combined with the pig fdDBM, incubated in vitro for 7 days and then implanted into the autologous bony defects (2x1x0.8cm ³) of dog jaws. BMSCs-fdDBM, unseeded fdDBM and empty defects served as control groups. At 3 or 6 monthes postimplantation,the dogs were sacrificed and the implants/jaws were harvested. The specimens were processed for radiographic bone-density analysis,histological , immuno- histochemical observation respectively. The data was analyzed with SAS 6.12 software for ANOVA. Results: New bone-like structure could be observed histologically in every implant specimen of every group. The density values of new bone in the implanting area treated with La ³⁺ was higher but there was no obvious statistics significance as compared with control. 6 monthes later the density values of new bone in BMSCs-fdDBM group and fdDBM group had no obvious difference (P>0.05) but obviously higher than that of empty control(P<0.05).Conclusion: La ³⁺at the concentation of 5.564ug/ml has no obvious negative effect on the osteogenesis of tissue engineering bone.

Key Words bone marrow stromal cells(BMSCs), tissue-engineering-bone,lanthanum chloride(La ³⁺),freeze-dried demineralized bone matrix(fdDBM)