Effect Of TGF-β₃ And Dental Pulp Stem Cells Combined With Bio-oss Bone Meal In Animal Bone Defect Repair

Objective TGF-β3 combined with dental pulp stem cells(DPSCs) and Bio-oss bone were positioned to the rabbit alveolar bone defect areas to explore the role of TGF-β3 induce new bone regeneration and reparative through DPSCs differentiations. Methods 1. DPSCs were isolated from pulp tissue of New Zealand rabbit’s incisors and molars and then cultured in vivo. 2. 24 experimental New Zealand rabbits were divided into blank group,control group 1, control group 2 and experimental group randomly( six rabbits/group). 10*4*4mm alveolar bone defect were made in animal mandibular edentulous artificially. In blank group, the defect was filled with 0.25 g Bio-oss powder mixed by PBS 20μL only;while the defect was filled with 250ng/μL TGF-β3 20μL and 0.25 g Bio-oss powder in control group1 and 1×108 /L DPSCs 20μL and 0.25 g Bio-oss powder in control group2; In the experimental group the defect was filled with 250ng/μL TGF-β3 20μL, 1×108 /L DPSCs 20μL and 0.25 g Bio-oss powder. The sterilized alveolar bone tissue were collected for paraffin section. HE staining and immunohistochemical detection of bone sialoprotein(BSP), osteocalcin(OC) and Type I collagen(COL-Ⅰ) were performed after 6 weeks later.Results 1) The primary cultured immature rabbit dental pulp cells were fibroblast liked, subcultured cells were basically the same as primary cultured cells under light microscope, young rabbit dental pulp cells subcultured in vitro still has good ability of proliferation. 2) HE staining: 6 weeks later after surgery, the blank group had no obvious bone formation; the control group1 showed few capillary, a small amount of trabecular bone while a small amount of osteoblasts and a small amount of blood capillary was found in control group2; In experimental group, bone defect area showed a large amount of capillary and a lot of bone cells, a significant increase in the amount of new bone plate.3) Immunohistochemical: the expression of BSP in experimental group(0.258±0.035) was higher( 0.192±0.030),( 0.215±0.026) and(0.231±0.052) in blank group, control group1 and control group2, respectively(P<0.05). the expression of OC was in blank group, control group1 and control group2 with(0.243±0.037),(0.272±0.058)and(0.275±0.046),and in experimental group is higher with(0.287±0.039),respectively(P<0.05); while the expression of COL-I in experimental group(0.237±0.059) was higher(0.135±0.026),(0.151±0.033)and(0.176±0.028) in blank group, control group1 and control group2, respectively(P<0.05)Conclusions 1) The DPSCs in this study has strong proliferation ability and stable biological activity, can meet the need of a large number of long-term culture. 2) Exogenous TGF-β3 and DPSCs can effectively promote the repair of defect, which provide a theoretical basis for the subsequent clinical experiments.